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Default Has anyone ever replaced their conventional furnace fan motor with anECM motor?


Just wondering if anyone has replaced their conventional furnace /
HVAC fan motor (PSC, single phase, etc) with one of the new ECM motors
to realize a reduction in your electricity bill.

Does anyone know what the "over-the-counter" cost is of these motors?

Also, do ECM motors generate electrical or RF noise that is either
radiated by the motor or fed back into the household wiring, thereby
messing up AM radio reception?
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Default Has anyone ever replaced their conventional furnace fan motorwith an ECM motor?

On Dec 21, 5:09*pm, Some Guy wrote:
Just wondering if anyone has replaced their conventional furnace /
HVAC fan motor (PSC, single phase, etc) with one of the new ECM motors
to realize a reduction in your electricity bill.

Does anyone know what the "over-the-counter" cost is of these motors?

Also, do ECM motors generate electrical or RF noise that is either
radiated by the motor or fed back into the household wiring, thereby
messing up AM radio reception?


What is an ECM motor?
Just a few thoughts.
Most conventional induction motors don't get that warm, so how much
electricity are they wasting?
Also; let's say that it is a 200 watt (quarter horsepower motor?) and
you can 'save' one quarter of that consumption.
Also the motor runs half the time?
So saving = 0.05 kilowatts x 24/2 = 0.6 kilowatt hours per day.
At 10 cents per k.watt.hr that = 6 cents per day. Roughly $25 per
year?
Versus cost of new motor?
On other hand that 'wasted' electricity is dissipated within the house
as heat so the furnace would have to run a few more minutes, burning a
little more oil/gas each time to compensate?
Might realise more gains by making furnace itself more efficient?
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Default Has anyone ever replaced their conventional furnace fan motor with an ECM motor?

terry wrote:
On Dec 21, 5:09 pm, Some Guy wrote:
Just wondering if anyone has replaced their conventional furnace /
HVAC fan motor (PSC, single phase, etc) with one of the new ECM
motors to realize a reduction in your electricity bill.

Does anyone know what the "over-the-counter" cost is of these motors?

Also, do ECM motors generate electrical or RF noise that is either
radiated by the motor or fed back into the household wiring, thereby
messing up AM radio reception?


What is an ECM motor?
Just a few thoughts.
Most conventional induction motors don't get that warm, so how much
electricity are they wasting?
Also; let's say that it is a 200 watt (quarter horsepower motor?) and
you can 'save' one quarter of that consumption.
Also the motor runs half the time?
So saving = 0.05 kilowatts x 24/2 = 0.6 kilowatt hours per day.
At 10 cents per k.watt.hr that = 6 cents per day. Roughly $25 per
year?
Versus cost of new motor?
On other hand that 'wasted' electricity is dissipated within the house
as heat so the furnace would have to run a few more minutes, burning a
little more oil/gas each time to compensate?


But the motor is outside the conditioned-air area, so it won't affect the
heating/cooling.

Assuming the motor costs $200, according to your calculations you would
break even in only eight years.

However, there is the opportunity cost to consider. $200 in a savings
account instead of a new motor, at 6% interest, generates $12 per year,
making the savings only $13. At that rate, the break-even point occurs in
fifteen years.

Then there's the labor to install the motor, increased taxes, and other
variables.



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Default Has anyone ever replaced their conventional furnace fan motorwith an ECM motor?

On Dec 21, 1:46*pm, "HeyBub" wrote:
terry wrote:
On Dec 21, 5:09 pm, Some Guy wrote:
Just wondering if anyone has replaced their conventional furnace /
HVAC fan motor (PSC, single phase, etc) with one of the new ECM
motors to realize a reduction in your electricity bill.


Does anyone know what the "over-the-counter" cost is of these motors?


Also, do ECM motors generate electrical or RF noise that is either
radiated by the motor or fed back into the household wiring, thereby
messing up AM radio reception?


What is an ECM motor?
Just a few thoughts.
Most conventional induction motors don't get that warm, so how much
electricity are they wasting?
Also; let's say that it is a 200 watt (quarter horsepower motor?) and
you can 'save' one quarter of that consumption.
Also the motor runs half the time?
So saving = 0.05 kilowatts x 24/2 = 0.6 kilowatt hours per day.
At 10 cents per k.watt.hr that = 6 cents per day. Roughly $25 per
year?
Versus cost of new motor?
On other hand that 'wasted' electricity is dissipated within the house
as heat so the furnace would have to run a few more minutes, burning a
little more oil/gas each time to compensate?


But the motor is outside the conditioned-air area, so it won't affect the
heating/cooling.

Assuming the motor costs $200, according to your calculations you would
break even in only eight years.

However, there is the opportunity cost to consider. $200 in a savings
account instead of a new motor, at 6% interest, generates $12 per year,
making the savings only $13. At that rate, the break-even point occurs in
fifteen years.

Then there's the labor to install the motor, increased taxes, and other
variables.- Hide quoted text -

- Show quoted text -


Where can you get a 600$ vsdc motor for 200?
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Default Has anyone ever replaced their conventional furnace fan motor with an ECM motor?

ransley wrote:
On Dec 21, 1:46 pm, "HeyBub" wrote:
terry wrote:
On Dec 21, 5:09 pm, Some Guy wrote:
Just wondering if anyone has replaced their conventional furnace /
HVAC fan motor (PSC, single phase, etc) with one of the new ECM
motors to realize a reduction in your electricity bill.


Does anyone know what the "over-the-counter" cost is of these
motors?


Also, do ECM motors generate electrical or RF noise that is either
radiated by the motor or fed back into the household wiring,
thereby messing up AM radio reception?


What is an ECM motor?
Just a few thoughts.
Most conventional induction motors don't get that warm, so how much
electricity are they wasting?
Also; let's say that it is a 200 watt (quarter horsepower motor?)
and you can 'save' one quarter of that consumption.
Also the motor runs half the time?
So saving = 0.05 kilowatts x 24/2 = 0.6 kilowatt hours per day.
At 10 cents per k.watt.hr that = 6 cents per day. Roughly $25 per
year?
Versus cost of new motor?
On other hand that 'wasted' electricity is dissipated within the
house as heat so the furnace would have to run a few more minutes,
burning a little more oil/gas each time to compensate?


But the motor is outside the conditioned-air area, so it won't
affect the heating/cooling.

Assuming the motor costs $200, according to your calculations you
would break even in only eight years.

However, there is the opportunity cost to consider. $200 in a savings
account instead of a new motor, at 6% interest, generates $12 per
year, making the savings only $13. At that rate, the break-even
point occurs in fifteen years.

Then there's the labor to install the motor, increased taxes, and
other variables.- Hide quoted text -

- Show quoted text -


Where can you get a 600$ vsdc motor for 200?


Arghh! I read 200 watts as 200 dollars. Sorry.

Multiply all my calculations by three (45 years to recover the expense). As
for your actual question, I guess I could get a $600 motor for $200 from
someone who was silly enough to attempt this project.




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Default Has anyone ever replaced their conventional furnace fan motor withan ECM motor?

HeyBub wrote:

Most conventional induction motors don't get that warm, so how
much electricity are they wasting?


They don't get warm because in a furnace, they're constantly being
cooled by the return airflow hitting them.

In general, from what I've read, a 1/4 to 1/2 hp PSC furnace motor is
shedding 150 to 300 watts of heat energy when in use.

Also; let's say that it is a 200 watt (quarter horsepower motor?)
and you can 'save' one quarter of that consumption.


At 100% efficiency, 1 hp = 746 watts. Since efficiency falls with
motor size, a 1/4 hp motor is at best 50% efficient (see reference
below). So it's consuming 373 watts (and shedding 186 watts as heat).

I pay 10.6 cents per kw-hour (about 60% of that is for the electricity
itself, and the other 40% is for other charges related to it's
delivery to me, as well as gov't taxes). In the summer, I'm running
my furnace fan constantly. For the average month, that's 730 hours.

For a motor that's using 373 watts for 730 hours, that's 272
kw-hours. At 10.6 cents per kw-hour, that's $28.83 per month.

Given a usage profile that has me running my fan for 100% during July
and August, and tailing off to 20% in February, I project an average
monthly usage of 49% for the entire year. That's about 4300 hours,
which works out to 1600 kw-hours, which works out to $170.

So if I had a conventional 1/4 hp PSC fan motor (50% efficient)
running for 4300 hours per year, I'm going to pay $170 per year.

If the motor was 100% efficient, I'd be paying $85 - saving $85 per
year.

At best, for an ECM motor, I'm going to increase my efficiency by 25%
(to 75%), so I'm going to save $42 per year.

I'd be saving more if I had a bigger motor, possibly saving $85 per
year if this was a comparison using 1/2 hp motors.

So what is the "over-the-counter" cost of a single speed 1/4 or 1/2 hp
ECM motor?

Are there any HVAC jobbers here that can answer that?

------------------------

http://www.eere.energy.gov/buildings...s_analysis.pdf

Good information really starts on page 13.

Capacitor-start, 4-pole motors have efficiencies from 50% to 65% (1/4,
1/3 and 1/2 hp) with efficiency increasing along with motor hp.

------------------------

On other hand that 'wasted' electricity is dissipated within
the house as heat so the furnace would have to run a few more
minutes, burning a little more oil/gas each time to compensate?


Most fan usage happens in conjunction with household cooling - not
heating.

During the non-heating seasons you are going to be running the fan -
sometimes without the A/C going.

I estimate that out of my hypothetical 4300 hours of fan use per year,
1640 hours will happen with the furnace on (about 38% of the time).
Where I live, the climate is similar to Detroit, Buffalo or Toronto.
Further south, more fan use will be for cooling than my projection of
62%. Based on this, the heat shed by the fan motor is not beneficial
or desirable most of the time.

But the motor is outside the conditioned-air area, so it won't
affect the heating/cooling.


The motor is *inside* the house. And it's placed directly in the
circulating air stream. So of course 100% of the heat it's shedding
will be transfered to the interior of the living space of the house.

Assuming the motor costs $200, according to your calculations
you would break even in only eight years.


Assuming my savings are between $40 and $80 per year (say, $60) and if
the motor costs $180 then it will take 3 years for payback. If the
motor is $240, then payback will be 4 years. If the motor is $480,
then payback will be 8 years.

The idea of earning interest on the money is nice, except that most
likely electricity costs will likely also rise, perhaps in a similar
way as your proposed 6%, so the opportunity cost factor will be a
wash. Especially given the volitile nature of the stock markets, and
declining interest rates. The S&P is up only 4.5% now vs the start of
the year.

Then there's the labor to install the motor,


That was going to be done by yours truly, so that's not a factor.

increased taxes,


Not sure what you mean by that.
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Default Has anyone ever replaced their conventional furnace fan motor with an ECM motor?

Fri, 21 Dec 2007 13:46:20 -0600 from HeyBub :
However, there is the opportunity cost to consider. $200 in a savings
account instead of a new motor, at 6% interest, generates $12 per year,
making the savings only $13.


Don't forget that interest is taxable, not to mention that a 6%
savings account is not realistic. Bankrate.com says CD rates are
still around 5% but likely to drop soon; a savings account would be
below that.

Figure 4% savings account, 28% tax bracket. Interest that you get to
keep is $8 times 0.72 a year, $5.76, so the savings would be $19.24 a
year and the payback period would be ten years and a few months.

Unless, of course, you're able to take advantage of some program that
subsidizes replacing inefficient equipment with efficient equipment.
Then the payback would be shorter.

--
Stan Brown, Oak Road Systems, Tompkins County, New York, USA
http://OakRoadSystems.com/
"If there's one thing I know, it's men. I ought to: it's
been my life work." -- Marie Dressler, in /Dinner at Eight/
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Default Has anyone ever replaced their conventional furnace fan motor with an ECM motor?

On Fri, 21 Dec 2007 09:09:25 -0500, Some Guy wrote:

Just wondering if anyone has replaced their conventional furnace /
HVAC fan motor (PSC, single phase, etc) with one of the new ECM motors
to realize a reduction in your electricity bill.

You'll never recoup the cost. Wait for the unit to wear out and then replace
it with something more efficient. If the entire unit is hopelessly inefficient,
then retrofitting makes no sense; replace the entire unit.


Does anyone know what the "over-the-counter" cost is of these motors?

Does anybody know how to use a web search tool?


Also, do ECM motors generate electrical or RF noise that is either
radiated by the motor or fed back into the household wiring, thereby
messing up AM radio reception?

Probably not; the motor is likely to be inside a metal housing.
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Default Has anyone ever replaced their conventional furnace fan motorwith an ECM motor?

On Dec 21, 9:14*am, AZ Nomad wrote:
On Fri, 21 Dec 2007 09:09:25 -0500, Some Guy wrote:
Just wondering if anyone has replaced their conventional furnace /
HVAC fan motor (PSC, single phase, etc) with one of the new ECM motors
to realize a reduction in your electricity bill.


You'll never recoup the cost. *Wait for the unit to wear out and then replace
it with something more efficient. *If the entire unit is hopelessly inefficient,
then retrofitting makes no sense; *replace the entire unit.

Does anyone know what the "over-the-counter" cost is of these motors?


Does anybody know how to use a web search tool?

Also, do ECM motors generate electrical or RF noise that is either
radiated by the motor or fed back into the household wiring, thereby
messing up AM radio reception?


Probably not; *the motor is likely to be inside a metal housing.


you need the electronics to run it, you cant just replace it my Lennox
guy said
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Default Has anyone ever replaced their conventional furnace fan motor withan ECM motor?

ransley wrote:

Just wondering if anyone has replaced their conventional

furnace / HVAC fan motor (PSC, single phase, etc) with one
of the new ECM motors to realize a reduction in your
electricity bill.


you need the electronics to run it, you cant just replace it my
Lennox guy said


I'm pretty sure that's not correct.

From what I can tell, all the electronics are inside the motor. You
hook up the main AC supply directly to the motor, just like a
conventional AC motor.


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Default Has anyone ever replaced their conventional furnace fan motor with an ECM motor?

"Some Guy" wrote in message ...
ransley wrote:

Just wondering if anyone has replaced their conventional
furnace / HVAC fan motor (PSC, single phase, etc) with one
of the new ECM motors to realize a reduction in your
electricity bill.


you need the electronics to run it, you cant just replace it my
Lennox guy said


I'm pretty sure that's not correct.

From what I can tell, all the electronics are inside the motor. You
hook up the main AC supply directly to the motor, just like a
conventional AC motor.


I don't think he was talking about the electronics of the motor.
Conventional motors were either ON or OFF and coincided with heat or cooling
on or off with a thermostatic delay. The newer ECM motors have a control
panel that changes the speed of the blower but at the same time controlling
the furnace heat output or the A/C compressor speed. Usually it is just a
two stage where there is a low and a high heat or A/C. I don't think you'd
get the full benefit by just switching motors if it didn't match the control
panel, burner and compressor.

-al sung
Rapid Realm Technology, Inc.
Hopkinton, MA


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Default Has anyone ever replaced their conventional furnace fan motor withan ECM motor?

Alan Sung wrote:

From what I can tell, all the electronics are inside the motor.
You hook up the main AC supply directly to the motor, just like
a conventional AC motor.


I don't think he was talking about the electronics of the motor.
Conventional motors were either ON or OFF and coincided with heat
or cooling on or off with a thermostatic delay. The newer ECM motors
have a control panel


As part of OEM equipment built into a furnace, an ECM motor will be
connected to a control panel.

As a replacement part bought over-the-counter, they most probably will
not come with any such panel.

There will most certainly be more connections on them for wires other
than household 120 AC power.

There may also be dip-switches or jumpers on them. Presumably it
would also come with a data sheet or wiring diagram.

that changes the speed of the blower but at the same time
controlling the furnace heat output or the A/C compressor
speed.


An HVAC maker can choose to use an ECM motor as a single-speed, or
maybe 2 speed, or continuously variable speed while at the same time
altering the heat output of the furnace (or changing the speed of the
compressor for AC) if they want to modulate the heat output of the
furnace and modulate the blower fan speed at the same time.

But it's still the case that an ECM motor is touted as being more
efficient *at all speeds and loads* compared to a PSC motor.

So even if I just use an ECM motor as a drop-in replacement for a PSC
motor, and wire the ECM motor for single-speed operation (which
theoretically shouldn't require an external controller board), then I
should realize some savings on my electrical bill.

And if I have the knowledge, I can rig my own control method such that
I can vary the fan speed at will. I could, for example, rig a pot or
a switch beside my thermostat so when I'm running the fan only for
circulation, I can turn down the speed (and realize even more savings
when compared to my PSC motor).

I don't think you'd get the full benefit by just switching motors
if it didn't match the control panel, burner and compressor.


If my current HVAC setup is operating such that I would not gain any
increase in "comfort" by having a variable-speed blower fan, then a
variable-speed motor would not be of any interest to me.

However, ECM refers to a particular type of motor technology. ECM
does not defacto mean variable speed. PSC motors can also be rigged
for variable speed operation too (with the appropriate external
controller).

The issue of a controller board keeps cropping up in this thread, and
it's a red herring.
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Default Has anyone ever replaced their conventional furnace fan motor withan ECM motor?

AZ Nomad wrote:

Just wondering if anyone has replaced their conventional furnace
/ HVAC fan motor (PSC, single phase, etc) with one of the new
ECM motors to realize a reduction in your electricity bill.


You'll never recoup the cost. Wait for the unit to wear out and...


Conventional small AC motors (fractional HP motors) are VERY
inefficient at converting electricity into motion. I've seen numbers
around 50% efficiency.

Many new furnaces today come with ECM motors because furnace fans run
longer (higher duty cycle) in modern HVAC systems today vs 20+ years
ago.

If the cost of an ECM motor is, say, less than $200 (for the
do-it-yourself-er) then it's highly likely that just replacing a
conventional AC motor with an ECM motor in an existing furnace would
pay itself back in 1 to 2 years - plus you have the existing motor as
a backup if or when the ECM motor breaks down.

If the entire unit is hopelessly inefficient,
then retrofitting makes no sense;


There are many mid-efficiency (80%) furnaces out there that DON't have
ECM motors, and there are many older furnaces that with simple
additions and modifications to intake and exhaust ducting (and by
turning down the burners and adjusting the burner primary air baffles)
can bring them to near 80% efficiency. You can convert a 30-year-old
60% efficient furnance to closed-combustion with some ducting and
modification to the cabinet's venting for example.

Does anyone know what the "over-the-counter" cost is of
these motors?


Does anybody know how to use a web search tool?


Nobody's posting any over-the-counter or "cash'n'carry" prices for
these motors on their websites.

I don't think too many of them are being sold for retro-fit or
non-HVAC systems.

In fact, there may even be supply shortages such that all production
is going straight to HVAC manufacturers.

Also, do ECM motors generate electrical or RF noise that is
either radiated by the motor or fed back into the household
wiring, thereby messing up AM radio reception?


Probably not; the motor is likely to be inside a metal housing.


My experience with electronically-controlled, variable-speed AC motors
(that you find in some treadmills and science-labs fume hoods) is that
they are extremely noisy (EM/RF noise) and without a lot of filtering
they inject a lot of noise back into the main supply wiring.

If there is a lot of high-current switching going on inside an ECM
motor, then I would think they too would be electrically noisy.
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Default Has anyone ever replaced their conventional furnace fan motorwith an ECM motor?

On Dec 21, 10:34*am, Some Guy wrote:
AZ Nomad wrote:
Just wondering if anyone has replaced their conventional furnace
/ HVAC fan motor (PSC, single phase, etc) with one of the new
ECM motors to realize a reduction in your electricity bill.

You'll never recoup the cost. *Wait for the unit to wear out and...


Conventional small AC motors (fractional HP motors) are VERY
inefficient at converting electricity into motion. *I've seen numbers
around 50% efficiency.

Many new furnaces today come with ECM motors because furnace fans run
longer (higher duty cycle) in modern HVAC systems today vs 20+ years
ago.

If the cost of an ECM motor is, say, less than $200 (for the
do-it-yourself-er) then it's highly likely that just replacing a
conventional AC motor with an ECM motor in an existing furnace would
pay itself back in 1 to 2 years - plus you have the existing motor as
a backup if or when the ECM motor breaks down.

If the entire unit is hopelessly inefficient,
then retrofitting makes no sense; *


There are many mid-efficiency (80%) furnaces out there that DON't have
ECM motors, and there are many older furnaces that with simple
additions and modifications to intake and exhaust ducting (and by
turning down the burners and adjusting the burner primary air baffles)
can bring them to near 80% efficiency. *You can convert a 30-year-old
60% efficient furnance to closed-combustion with some ducting and
modification to the cabinet's venting for example.



This furnace "modification" suggestion sounds very dubious and full of
obvious and potentially serious drawbacks to me. Like people
screwing around and winding up killing a house full of people with CO
or fire. If you have a 60% 30 year old furnace and it's worth
increasing it's efficiency, then it's worth getting a new furnace.





Does anyone know what the "over-the-counter" cost is of
these motors?


Does anybody know how to use a web search tool?


Nobody's posting any over-the-counter or "cash'n'carry" prices for
these motors on their websites.

I don't think too many of them are being sold for retro-fit or
non-HVAC systems.

In fact, there may even be supply shortages such that all production
is going straight to HVAC manufacturers.

Also, do ECM motors generate electrical or RF noise that is
either radiated by the motor or fed back into the household
wiring, thereby messing up AM radio reception?

Probably not; *the motor is likely to be inside a metal housing.


My experience with electronically-controlled, variable-speed AC motors
(that you find in some treadmills and science-labs fume hoods) is that
they are extremely noisy (EM/RF noise) and without a lot of filtering
they inject a lot of noise back into the main supply wiring.

If there is a lot of high-current switching going on inside an ECM
motor, then I would think they too would be electrically noisy.


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Default Has anyone ever replaced their conventional furnace fan motor withan ECM motor?

wrote:

You can convert a 30-year-old 60% efficient furnance to
closed-combustion with some ducting and modification to
the cabinet's venting for example.


This furnace "modification" suggestion sounds very dubious


Not really. You can create a closed-loop for the intake air very
simply with the appropriate additions of ductwork that takes outside
air directly into the cabinet and sealing the cabinet so that the
combustion side can't mix with household air. The secondary flue air
intake (directly below where the flue starts) can also be sealed and
ducted so that it pulls air from a dedicated outside supply duct and
not from household air near the furnace. So in this scenario no
outside air can enter the house through the flue, and no combustion
products or gasses can enter the interior air of the house.

That is exactly what mid and high efficiency furnaces do, and there's
no reason the same mods can't be done with low efficiency furnaces
that are 20+ years old.

Like people screwing around and winding up killing a house
full of people with CO or fire.


You're actually making it safer by creating a closed loop. By doing
so, there is no way that the blower can suck air back through the
flue. Given an un-modified low-efficiency furnace, that's exactly
what can happen if the house is sealed too tightly and too many
exhaust fans are operating in the house.

If you have a 60% 30 year old furnace and it's worth
increasing it's efficiency, then it's worth getting a
new furnace.


The furnaces made today are riddled with problems with short-lived
heat exchangers, sensors and electronic controllers.

Have a look at this site for an example of a poorly-designed secondary
heat exchanger:

http://furnaceclaims.com/

It's generally accepted within pro hvac circles that there are many
new components, ideas and manufacturing techniques cropping up in
furnaces over the past few years that don't have the benefit of years
of field longevity and durability testing.


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Default Has anyone ever replaced their conventional furnace fan motorwith an ECM motor?

On Dec 21, 5:26*pm, Some Guy wrote:
wrote:
You can convert a 30-year-old 60% efficient furnance to
closed-combustion with some ducting and modification to
the cabinet's venting for example.


This furnace "modification" suggestion sounds very dubious


Not really. *You can create a closed-loop for the intake air very
simply with the appropriate additions of ductwork that takes outside
air directly into the cabinet and sealing the cabinet so that the
combustion side can't mix with household air. *The secondary flue air
intake (directly below where the flue starts) can also be sealed and
ducted so that it pulls air from a dedicated outside supply duct and
not from household air near the furnace. *So in this scenario no
outside air can enter the house through the flue, and no combustion
products or gasses can enter the interior air of the house.

That is exactly what mid and high efficiency furnaces do, and there's
no reason the same mods can't be done with low efficiency furnaces
that are 20+ years old.

Like people screwing around and winding up killing a house
full of people with CO or fire. *


You're actually making it safer by creating a closed loop. *By doing
so, there is no way that the blower can suck air back through the
flue. *Given an un-modified low-efficiency furnace, that's exactly
what can happen if the house is sealed too tightly and too many
exhaust fans are operating in the house.

If you have a 60% 30 year old furnace and it's worth
increasing it's efficiency, then it's worth getting a
new furnace.


The furnaces made today are riddled with problems with short-lived
heat exchangers, sensors and electronic controllers.

Have a look at this site for an example of a poorly-designed secondary
heat exchanger:

http://furnaceclaims.com/

It's generally accepted within pro hvac circles that there are many
new components, ideas and manufacturing techniques cropping up in
furnaces over the past few years that don't have the benefit of years
of field longevity and durability testing.


No it isn't generally accepted. What you're referring to isn't
unsolved problems, what it's called is "planned obsolescence". If it
doens't break they can't sell you a new one. The hvac industry is a
relative late-comer to that game, thats all.
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Default Has anyone ever replaced their conventional furnace fan motor with an ECM motor?


"Some Guy" wrote in message ...

Just wondering if anyone has replaced their conventional furnace /
HVAC fan motor (PSC, single phase, etc) with one of the new ECM motors
to realize a reduction in your electricity bill.

Does anyone know what the "over-the-counter" cost is of these motors?

Also, do ECM motors generate electrical or RF noise that is either
radiated by the motor or fed back into the household wiring, thereby
messing up AM radio reception?


http://www.ccht-cctr.gc.ca/ecm_e.html

It's a Canadian study but shows some benefits

PV


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Default Has anyone ever replaced their conventional furnace fan motorwith an ECM motor?

On Dec 21, 8:09*am, Some Guy wrote:
Just wondering if anyone has replaced their conventional furnace /
HVAC fan motor (PSC, single phase, etc) with one of the new ECM motors
to realize a reduction in your electricity bill.

Does anyone know what the "over-the-counter" cost is of these motors?

Also, do ECM motors generate electrical or RF noise that is either
radiated by the motor or fed back into the household wiring, thereby
messing up AM radio reception?


ECM motors require a control signal in addition to line voltage.
Also, you cannot just wire the power to the motor, it requires a pre-
wired molex plug specifically designed to plug into the motor.
Likewise for the control signal. A control board is also required,
that is, unless you know how to hot wire the motor control signal.

There is however a new ECM design avialable called the "Evergreen AH".
It is specifically designed as a retrofit for PSC motors. I have no
idea how much they cost. They are not rated at this time for furnaces,
air handlers only. This limitation can also be worked around by
someone with the correct skills.

The retrofit isn't really practical from any standpoint, even though
it is possible to do.






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Default Has anyone ever replaced their conventional furnace fan motor withan ECM motor?

hvacrmedic wrote:

There is however a new ECM design avialable called the
"Evergreen AH". It is specifically designed as a retrofit
for PSC motors.


http://www.thedealertoolbox.com/ever...82d3b5 e1cd0d

They are not rated at this time for furnaces, air handlers only.


What's the difference between a furnace-fan motor and an
air-handler-fan motor?

The retrofit isn't really practical from any standpoint, even
though it is possible to do.


Seems you're wrong. It's being marketed directly to HVAC repair shops
exactly as a replacement for furnace PSC motors.

"Evergreen AH is the world’s first high-efficiency ECM replacement
motor that is designed to replace factory PSC blower motors in
residential air handlers. That means you can now offer your
customers the comfort and efficiency of ECM in an easy-to-install
replacement motor.

Built from the same trusted, field-proven ECM technology that is
found in millions of OEM systems nationwide, Evergreen AH uses up
to 25% fewer watts in operating mode and up to 74% fewer Watts
than a PSC motor in constant fan."

http://www.thedealertoolbox.com/serv...82d3b5e 1cd0d

See also:

http://www.evergreenmotor.com/faq.php


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Default Has anyone ever replaced their conventional furnace fan motorwith an ECM motor?

On Dec 21, 5:42 pm, Some Guy wrote:
hvacrmedic wrote:
There is however a new ECM design avialable called the
"Evergreen AH". It is specifically designed as a retrofit
for PSC motors.


http://www.thedealertoolbox.com/ever...=a3eeeffb9e20d...

They are not rated at this time for furnaces, air handlers only.


What's the difference between a furnace-fan motor and an
air-handler-fan motor?


There is no difference in the motors. It's the control systems that
are different.


The retrofit isn't really practical from any standpoint, even
though it is possible to do.


Seems you're wrong. It's being marketed directly to HVAC repair shops
exactly as a replacement for furnace PSC motors.


I believe I said as much. This has nothing to do with the practicality
of buying one.


"Evergreen AH is the world's first high-efficiency ECM replacement
motor that is designed to replace factory PSC blower motors in
residential air handlers. That means you can now offer your
customers the comfort and efficiency of ECM in an easy-to-install
replacement motor.

Built from the same trusted, field-proven ECM technology that is
found in millions of OEM systems nationwide, Evergreen AH uses up
to 25% fewer watts in operating mode and up to 74% fewer Watts
than a PSC motor in constant fan."

http://www.thedealertoolbox.com/serv...PSESSID=a3eeef...

See also:

http://www.evergreenmotor.com/faq.php


Quoting a salespitch isn't the equivalent of enlightenment. You
didn't even know that the thing existed until a few minutes ago. In
fact you thought (very wrongly) that you could throw a standard ECM
motor into any old unit. You should spend some time googling reliable
resources and less time stating your own uneducated opinions.
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Default Has anyone ever replaced their conventional furnace fan motor withan ECM motor?

hvacrmedic wrote:

There is no difference in the motors. It's the control systems
that are different.


What -

On
Off

What else do you need for a control system?

Quoting a salespitch isn't the equivalent of enlightenment.
You didn't even know that the thing existed until a few minutes ago.


I've known about ECM motors for some time.

In fact you thought (very wrongly) that you could throw a
standard ECM motor into any old unit.


What is a "standard" ECM motor?

I know that there are drop-in ECM motors - even if they have
dip-switches to set their operation in the absence of a control
signal.

The Evergreen unit isin't the only drop-in replacement.
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Default Has anyone ever replaced their conventional furnace fan motorwith an ECM motor?

On Dec 21, 7:42*pm, Some Guy wrote:
hvacrmedic wrote:
There is no difference in the motors. It's the control systems
that are different.


What -

On
Off

What else do you need for a control system?


More than the two words on and off.


Quoting a salespitch isn't the equivalent of enlightenment.
You didn't even know that the thing existed until a few minutes ago.


I've known about ECM motors for some time.


You've known they existed. Great.


In fact you thought (very wrongly) that you could throw a
standard ECM motor into any old unit. *


What is a "standard" ECM motor?


A "standard" ECM motor is an ECM motor that can be used to replace a
PSC motor. For the difference between these and the other ECM motors
in thier line-up, you can read the GE literature, or watch the videos
listed here.

http://www.thedealertoolbox.com/training-videos.php


I know that there are drop-in ECM motors - even if they have
dip-switches to set their operation in the absence of a control
signal.

The Evergreen unit isin't the only drop-in replacement.


So what's stopping you from dropping one in? I don't know what you're
trying to accomplish, but you seem to be posting a lot of opinions in
this and other threads that FWIW have been mostly empirically
incorrect. I'm done with this particular training session. Come up
with another topic that's a bit more interesting.



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Default Has anyone ever replaced their conventional furnace fan motorwith an ECM motor?

Some Guy wrote:
Just wondering if anyone has replaced their conventional furnace /
HVAC fan motor (PSC, single phase, etc) with one of the new ECM motors
to realize a reduction in your electricity bill.

Does anyone know what the "over-the-counter" cost is of these motors?

Also, do ECM motors generate electrical or RF noise that is either
radiated by the motor or fed back into the household wiring, thereby
messing up AM radio reception?

Hi,
Don't even bother. It is DC servorized motor with matching control
logic board. High efficiency furnaces are made to take advantage of
this variable speed motor. Also they are not as reliable as ordinary
motor. If you don't understand how closed loop DC servo motor works..

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Default Has anyone ever replaced their conventional furnace fan motorwithan ECM motor?

Tony Hwang wrote:

Just wondering if anyone has replaced their conventional furnace
/ HVAC fan motor (PSC, single phase, etc) with one of the new
ECM motors to realize a reduction in your electricity bill.


Don't even bother. It is DC servorized motor with matching control
logic board. High efficiency furnaces are made to take advantage
of this variable speed motor.


Everything you're saying is true, but it doesn't mean that
fundamentally ECM motors are more efficient regardless in what type of
furnace they're used in.

Even if all I do is use it as a constant-speed replacement for a 50%
efficient PSC motor, it will use less electricity.

The question is - how much, and what is the over-the-counter cost of a
suitable ECM motor (not the HVAC-contractor-installed price).

Also they are not as reliable as ordinary motor.


That is probably true, and along the lines of planned obsolescence
that's designed into modern residential HVAC systems.


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Default Has anyone ever replaced their conventional furnace fan motorwithan ECM motor?

On Dec 21, 11:04*pm, Some Guy wrote:
Tony Hwang wrote:
Just wondering if anyone has replaced their conventional furnace
/ HVAC fan motor (PSC, single phase, etc) with one of the new
ECM motors to realize a reduction in your electricity bill.

Don't even bother. It is DC servorized motor with matching control
logic board. High efficiency furnaces are made to take advantage
of this variable speed motor.


Everything you're saying is true, but it doesn't mean that
fundamentally ECM motors are more efficient regardless in what type of
furnace they're used in.

Even if all I do is use it as a constant-speed replacement for a 50%
efficient PSC motor, it will use less electricity.

The question is - how much, and what is the over-the-counter cost of a
suitable ECM motor (not the HVAC-contractor-installed price).

Also they are not as reliable as ordinary motor.


That is probably true, and along the lines of planned obsolescence
that's designed into modern residential HVAC systems.


I've worked at and with a lot of companies engaged in all kinds of
product design during my career. But I never heard any discussion of
planned obsolence, which IMO is largely an urban legend. There is
a real tradeoff between what it costs to make, how much you can sell
it for, and longevity. In my experience, that is where the tradeoff
is made.
If you made a product that deliberately lasted 10 years, while it
could last 20, it wouldn't be long before a competitor whose product
did last 20 would start eating your market share because their product
was superior. That's how free markets work.

The typical funace lasts 20 years. Given the cost, that seems a
reasonable lifespan. How many customers would be willing to pay say
30% more for one that lasted another 5 years? Or 50% more for one
that lasted another 10? Most people don't even plan to be in their
homes that long today. Given that the energy situation and technology
is constantly evolving, I don't see a problem with the lifespan or
value proposition presented by today's furnaces.
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Default Has anyone ever replaced their conventional furnace fan motorwithan ECM motor?

On Dec 22, 8:03*am, wrote:
On Dec 21, 11:04*pm, Some Guy wrote:





Tony Hwang wrote:
Just wondering if anyone has replaced their conventional furnace
/ HVAC fan motor (PSC, single phase, etc) with one of the new
ECM motors to realize a reduction in your electricity bill.
Don't even bother. It is DC servorized motor with matching control
logic board. High efficiency furnaces are made to take advantage
of this variable speed motor.


Everything you're saying is true, but it doesn't mean that
fundamentally ECM motors are more efficient regardless in what type of
furnace they're used in.


Even if all I do is use it as a constant-speed replacement for a 50%
efficient PSC motor, it will use less electricity.


The question is - how much, and what is the over-the-counter cost of a
suitable ECM motor (not the HVAC-contractor-installed price).


Also they are not as reliable as ordinary motor.


That is probably true, and along the lines of planned obsolescence
that's designed into modern residential HVAC systems.


I've worked at and with a lot of companies engaged in all kinds of
product design during my career. *But I never heard any discussion of
planned obsolence, which IMO is largely an urban legend. * * There is
a real tradeoff between what it costs to make, how much you can sell
it for, and longevity. *In my experience, that is where the tradeoff
is made.
If you made a product that deliberately lasted 10 years, while it
could last 20, it wouldn't be long before a competitor whose product
did last 20 would start eating your market share because their product
was superior. * That's how free markets work.

The typical funace lasts 20 years. * Given the cost, that seems a
reasonable lifespan. * How many customers would be willing to pay say
30% more for one that lasted another 5 years? *Or 50% more for one
that lasted another 10? * Most people don't even plan to be in their
homes that long today. *Given that the energy situation and technology
is constantly evolving, I don't see a problem with the lifespan or
value proposition presented by today's furnaces.- Hide quoted text -

- Show quoted text -


"Not designed to last 30 years" is logically equivalent to "Designed
to last no more than 30 years". Like I said, it isn't necessarily a
concious desicion, but planned obselesence is precisely what it is.
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Default Has anyone ever replaced their conventional furnace fan motorwithan ECM motor?

On Dec 22, 8:16*am, hvacrmedic wrote:
On Dec 22, 8:03*am, wrote:





On Dec 21, 11:04*pm, Some Guy wrote:


Tony Hwang wrote:
Just wondering if anyone has replaced their conventional furnace
/ HVAC fan motor (PSC, single phase, etc) with one of the new
ECM motors to realize a reduction in your electricity bill.
Don't even bother. It is DC servorized motor with matching control
logic board. High efficiency furnaces are made to take advantage
of this variable speed motor.


Everything you're saying is true, but it doesn't mean that
fundamentally ECM motors are more efficient regardless in what type of
furnace they're used in.


Even if all I do is use it as a constant-speed replacement for a 50%
efficient PSC motor, it will use less electricity.


The question is - how much, and what is the over-the-counter cost of a
suitable ECM motor (not the HVAC-contractor-installed price).


Also they are not as reliable as ordinary motor.


That is probably true, and along the lines of planned obsolescence
that's designed into modern residential HVAC systems.


I've worked at and with a lot of companies engaged in all kinds of
product design during my career. *But I never heard any discussion of
planned obsolence, which IMO is largely an urban legend. * * There is
a real tradeoff between what it costs to make, how much you can sell
it for, and longevity. *In my experience, that is where the tradeoff
is made.
If you made a product that deliberately lasted 10 years, while it
could last 20, it wouldn't be long before a competitor whose product
did last 20 would start eating your market share because their product
was superior. * That's how free markets work.


The typical funace lasts 20 years. * Given the cost, that seems a
reasonable lifespan. * How many customers would be willing to pay say
30% more for one that lasted another 5 years? *Or 50% more for one
that lasted another 10? * Most people don't even plan to be in their
homes that long today. *Given that the energy situation and technology
is constantly evolving, I don't see a problem with the lifespan or
value proposition presented by today's furnaces.- Hide quoted text -


- Show quoted text -


"Not designed to last 30 years" is logically equivalent to "Designed
to last no more than 30 years". Like I said, it isn't necessarily a
concious desicion, but planned obselesence is precisely what it is.- Hide quoted text -

- Show quoted text -


Actually that number has been halved, 15 years being the present
value. Some even say 12, depending upon who you ask.

Is the cup half empty, or half full? The point of that being that
even though the systems are designed to last no more than 15 years, by
taking the stance that they are designed to last at least 15 years
you've convinced yourself that that means something different, when,
as I said, it is a perfectly equivalent view to planned obsolesence.

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Default Has anyone ever replaced their conventional furnace fan motorwithan ECM motor?

On Dec 22, 9:16*am, hvacrmedic wrote:
On Dec 22, 8:03*am, wrote:





On Dec 21, 11:04*pm, Some Guy wrote:


Tony Hwang wrote:
Just wondering if anyone has replaced their conventional furnace
/ HVAC fan motor (PSC, single phase, etc) with one of the new
ECM motors to realize a reduction in your electricity bill.
Don't even bother. It is DC servorized motor with matching control
logic board. High efficiency furnaces are made to take advantage
of this variable speed motor.


Everything you're saying is true, but it doesn't mean that
fundamentally ECM motors are more efficient regardless in what type of
furnace they're used in.


Even if all I do is use it as a constant-speed replacement for a 50%
efficient PSC motor, it will use less electricity.


The question is - how much, and what is the over-the-counter cost of a
suitable ECM motor (not the HVAC-contractor-installed price).


Also they are not as reliable as ordinary motor.


That is probably true, and along the lines of planned obsolescence
that's designed into modern residential HVAC systems.


I've worked at and with a lot of companies engaged in all kinds of
product design during my career. *But I never heard any discussion of
planned obsolence, which IMO is largely an urban legend. * * There is
a real tradeoff between what it costs to make, how much you can sell
it for, and longevity. *In my experience, that is where the tradeoff
is made.
If you made a product that deliberately lasted 10 years, while it
could last 20, it wouldn't be long before a competitor whose product
did last 20 would start eating your market share because their product
was superior. * That's how free markets work.


The typical funace lasts 20 years. * Given the cost, that seems a
reasonable lifespan. * How many customers would be willing to pay say
30% more for one that lasted another 5 years? *Or 50% more for one
that lasted another 10? * Most people don't even plan to be in their
homes that long today. *Given that the energy situation and technology
is constantly evolving, I don't see a problem with the lifespan or
value proposition presented by today's furnaces.- Hide quoted text -


- Show quoted text -


"Not designed to last 30 years" is logically equivalent to "Designed
to last no more than 30 years". Like I said, it isn't necessarily a
concious desicion, but planned obselesence is precisely what it is.- Hide quoted text -

- Show quoted text -



The notion of something being planned without it being a conscious
decision defies all logic. My main point is that Some Guy referred
to planned obsolescence designed into today's products. Which to
most people implies there is some specific planning on the part of
manufacturers that is different today to make sure the product only
lasts a given number of years and then fails so they have to buy
another one.

In reality, it's no different today than it ever was. Manufacturer's
are competing in a free economy and reacting to it. That includes
making trade-offs, as has always been done, about how long it makes
sense for a product to last vs how much it costs to build it and how
much people are willing to pay for it. If you want to call that
planned obsolescence, then we agree, but I think it's a poor choice of
words and it's nothing specific to today's products.
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Default Has anyone ever replaced their conventional furnace fan motorwith anECM motor?

wrote:

If you made a product that deliberately lasted 10 years, while it
could last 20, it wouldn't be long before a competitor whose
product did last 20 would start eating your market share because
their product was superior. That's how free markets work.


The problem is that nothing purchased by *anybody* will be kept for 20
years. That time-frame is too long.

It doesn't matter if it's a car, or roofing shingles, or furnaces, or
cell phones or TV's.

Once you get beyond 5 years, it's irrelevant if you could design it to
last 10 years or 20 years. It won't matter.

Most home owners putting a new furnace in a house today will not be
the same people living in the same house 10 years from now when the
furnace breaks down.

The HVAC industry is, and has been, working toward a goal of making
sure that just as each owner of a given house will probably have to
replace the roof once during the ownership of the house, he will also
have to replace the furnace too.

That is a different situation compared to 20 or 30 years ago, when the
original furnace installed in a new house back in 1965 - 1980 would
easily last 30+ years and the house would pass through the hands of 3
or 4 owners without needing a new furnace.

The typical funace lasts 20 years.


My parent's house was built in 1955 and they replaced it's original
forced-air natural gas furnace about 5 years ago. That's 45 years
with the same furnace.

My house was built in 1976 and has it's original natural gas furnace.
That's 32 years and counting.

The typical funace lasts 20 years.


So the HVAC industry is on target at reducing furnace lifespan down to
the time frame of the average length of home-ownership - about 7
years. Good for them.

Given the cost, that seems a reasonable lifespan.


It's a waste of energy and resources for an industry to design such a
product with an intentionally short lifespan. It runs counter to the
national interests on such scales as energy usage (to build it in the
first place) and environmental impact when it's taken to the landfill
when it's discarded.

You could make the same argument for other items, like wiring,
plumbing, fixtures, the bricks and 2x4 studs in the walls. Why do
they need to last 50+ years? Why not design the entire house and
every structural and functional element inside it so that it only
lasts 10 to 15 years? After all, I'm not going to live in the house
for more than 10 years - right?

And then watch the landfills get filled up when all those houses get
torn down and rebuilt every 15 or 20 years. That makes real good
sense - doesn't it?

How many customers would be willing to pay say 30% more for
one that lasted another 5 years? Or 50% more for one
that lasted another 10?


That's the crock - that thinking that it costs so much more to make it
last another 5 or 10 years.

It's the electronic items that fail and become absurdly (criminally)
expensive to fix that forces the removal of a furnace - not because
it's suffered an irreparable structural or mechanical failure. And as
home owners become dumber and dumber about how things work or how to
fix things for themselves, they will be at the mercy of contractors
and repair men.

Given that the energy situation and technology is
constantly evolving,


There's very little new in furnace design that wasn't known 50 years
ago. There is no constant evolution (at least not in North America).
In Japan, they have furnaces with built-in 1 kw electric generators to
provide some electrical co-generation that can supplement the
electricity supply for the house - and keep the blower running in the
case of complete power outages (like what's happening to thousands in
the central USA right now).


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Default Has anyone ever replaced their conventional furnace fan motorwithan ECM motor?

On Dec 22, 10:26*am, HVAC Guy wrote:
wrote:
If you made a product that deliberately lasted 10 years, while it
could last 20, it wouldn't be long before a competitor whose
product did last 20 would start eating your market share because
their product was superior. * That's how free markets work.


The problem is that nothing purchased by *anybody* will be kept for 20
years. *That time-frame is too long.

It doesn't matter if it's a car, or roofing shingles, or furnaces, or
cell phones or TV's.

Once you get beyond 5 years, it's irrelevant if you could design it to
last 10 years or 20 years. *It won't matter.

Most home owners putting a new furnace in a house today will not be
the same people living in the same house 10 years from now when the
furnace breaks down.


All of that I agree with. Which is exactly what I've been saying.
Manufacturers are simply reacting to what the market needs are.



The HVAC industry is, and has been, working toward a goal of making
sure that just as each owner of a given house will probably have to
replace the roof once during the ownership of the house, he will also
have to replace the furnace too.


Now that I'd like to see proof of.




That is a different situation compared to 20 or 30 years ago, when the
original furnace installed in a new house back in 1965 - 1980 would
easily last 30+ years and the house would pass through the hands of 3
or 4 owners without needing a new furnace.

The typical funace lasts 20 years.


My parent's house was built in 1955 and they replaced it's original
forced-air natural gas furnace about 5 years ago. *That's 45 years
with the same furnace.

My house was built in 1976 and has it's original natural gas furnace.
That's 32 years and counting.

The typical funace lasts 20 years.


So the HVAC industry is on target at reducing furnace lifespan down to
the time frame of the average length of home-ownership - about 7
years. *Good for them.



I'd like to see proof that the goal is to get lifespan down to 7
years.




Given the cost, that seems a reasonable lifespan. *


It's a waste of energy and resources for an industry to design such a
product with an intentionally short lifespan. *It runs counter to the
national interests on such scales as energy usage (to build it in the
first place) and environmental impact when it's taken to the landfill
when it's discarded.


What short lifespan are you referring to? 20 years for a furnace
seems like a reasonable compromise in terms of lifespan. And you
choose to totally ignore the energy usage that a 45 year old furnace
will waste compared to a new one? I'd say that will easily outweigh
the energy wasted by recycling it back to the scrap yard. Look at all
the environmental programs out there to encourage precisely this kind
of action. Utilities and govts are offering rebates for consumers to
encourage them to get a new furnace or AC system that is energy
efficient. That surely leads to more of the old ones going to the
metal scrap yard

And how many customers are going to be willing to pay significantly
more for a furnace that will last 45 years, without knowing how
improvements, energy sources, convenience features, etc will play out
over decades? I'll pay more for something if I think it's going to be
worth it and economically makes sense. And for me, 20-25 years is
the sweet spot for an HVAC system. I'm not going to shell out much,
if anything more for one that is supposed to last 45 years.



You could make the same argument for other items, like wiring,
plumbing, fixtures, the bricks and 2x4 studs in the walls. *Why do
they need to last 50+ years? *Why not design the entire house and
every structural and functional element inside it so that it only
lasts 10 to 15 years? *After all, I'm not going to live in the house
for more than 10 years - right?


Now this is just plain silly. Historically, there haven't been a lot
of improvements or changes in 2X4's, bricks, or the basic plumbing
system. There has been in HVAC though. Nor can they be replaced
with even remotely the ease of an HVAC system. As for things like
fixtures, I'd submit that few people today expect any of them to last
for 50+ years. People are used to dishwashers, ovens, etc lasting 15
years or so. Even faucets and sinks get changed long before 50
years. I wouldn't want the same style sink or faucet I had 50 years
ago. I just replaced my own kitchen sink which was 20 years old for
convenience and changing needs.


And then watch the landfills get filled up when all those houses get
torn down and rebuilt every 15 or 20 years. *That makes real good
sense - doesn't it?


Not an issue because it isn't happening and isn't going to.



How many customers would be willing to pay say 30% more for
one that lasted another 5 years? *Or 50% more for one
that lasted another 10? *


That's the crock - that thinking that it costs so much more to make it
last another 5 or 10 years.


You don't want it to last 5 more years. You keep referring to 45 or
50 years. And without knowing what it costs to manufacture specific
items, there is no way for you to know how much more anything costs to
build, it's pure speculation.



It's the electronic items that fail and become absurdly (criminally)
expensive to fix that forces the removal of a furnace - not because
it's suffered an irreparable structural or mechanical failure. *And as
home owners become dumber and dumber about how things work or how to
fix things for themselves, they will be at the mercy of contractors
and repair men.


Welcome to the modern world. Try going down to the dealer and seeing
how much a new computer or similar module costs for your car. Or some
parts for a refrigerator or stove.



Given that the energy situation and technology is
constantly evolving,


There's very little new in furnace design that wasn't known 50 years
ago. *


So, they had 95% efficient furnaces 50 years ago? I must have missed
that. Plus in many cases, people are using AC systems today as
opposed to 1957, aren't they? I suppose any old AC system that is
part of the whole picture and that is of similar age is peachy keen
too?


There is no constant evolution (at least not in North America).
In Japan, they have furnaces with built-in 1 kw electric generators to
provide some electrical co-generation that can supplement the
electricity supply for the house - and keep the blower running in the
case of complete power outages (like what's happening to thousands in
the central USA right now).


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Default Has anyone ever replaced their conventional furnace fan motorwithan ECM motor?

Some Guy wrote:
Tony Hwang wrote:


Just wondering if anyone has replaced their conventional furnace
/ HVAC fan motor (PSC, single phase, etc) with one of the new
ECM motors to realize a reduction in your electricity bill.



Don't even bother. It is DC servorized motor with matching control
logic board. High efficiency furnaces are made to take advantage
of this variable speed motor.



Everything you're saying is true, but it doesn't mean that
fundamentally ECM motors are more efficient regardless in what type of
furnace they're used in.

Even if all I do is use it as a constant-speed replacement for a 50%
efficient PSC motor, it will use less electricity.

The question is - how much, and what is the over-the-counter cost of a
suitable ECM motor (not the HVAC-contractor-installed price).


Also they are not as reliable as ordinary motor.



That is probably true, and along the lines of planned obsolescence
that's designed into modern residential HVAC systems.

Hi,
This type motor is known for failure mode for motor and controller going
out together. Most people who has this thing in their furnace, they take
out 10 year warranty for that part. If you buy and use it as constant
speed blower at an expense, that is fine for the purpose of experiment
but economy wise I don't think you'll recover initial cost and if it
fails......
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Default Has anyone ever replaced their conventional furnace fan motor withan ECM motor?

Tony Hwang wrote:

This type motor is known for failure mode for motor and
controller going out together. Most people who has this
thing in their furnace, they take out 10 year warranty
for that part.


That is all probably true.

If you buy and use it as constant speed blower at an
expense, that is fine for the purpose of experiment
but economy wise I don't think you'll recover initial
cost and if it fails......


In a previous post, I've already roughly calculated that I'd probably
save $40, possibly $60 per year if I changed my PSC motor for an ECM
motor.

The question that I continue to ask is: What is the
"over-the-counter" price of an ECM motor?

I can walk into any hardware or farm supply store and buy a 120v, 1/3
hp PSC motor (for $75 to $150).

Where do go when I want to pick up an ECM motor?

Who sells them "over the counter" ?
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Default Has anyone ever replaced their conventional furnace fan motorwith an ECM motor?

Some Guy wrote:
Tony Hwang wrote:


This type motor is known for failure mode for motor and
controller going out together. Most people who has this
thing in their furnace, they take out 10 year warranty
for that part.



That is all probably true.


If you buy and use it as constant speed blower at an
expense, that is fine for the purpose of experiment
but economy wise I don't think you'll recover initial
cost and if it fails......



In a previous post, I've already roughly calculated that I'd probably
save $40, possibly $60 per year if I changed my PSC motor for an ECM
motor.

The question that I continue to ask is: What is the
"over-the-counter" price of an ECM motor?

I can walk into any hardware or farm supply store and buy a 120v, 1/3
hp PSC motor (for $75 to $150).

Where do go when I want to pick up an ECM motor?

Who sells them "over the counter" ?

Hi,
Lennox is known for selling parts only to trade people. You can contact
other brand supply house or try on-line search. Another issue maybe
mechanically fitting it into your existing set up. Prepare to pay
over a grand for motor and controller. How much is electricity cost
where you are? I have locked in rate of 7 cents per KWH for next 5 years.
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