On Dec 10, 10:23*am, "Steve" wrote:
"Home Guy" wrote in ....
wrote:

The new furnace is a multispeed brushless DC motor

They are a heck of a lot more efficient than a crappy split cap
induction motor!!

Sometimes durability and longevity trumps efficiency.

Even if electric heat (on a per-therm basis) is twice the cost of
natural gas, that extra energy used by a PSC motor is beneficially used
by my house in the winter, and my PSC fan is running only maybe 25 to
33% of the time, not 100% of the time. *In the summer, when my fan is
running more often, it's running at full speed - something that I would
also ask an ECM motor to do, and for which the ECM motor does not have
as much of an efficiency advantage over a PSC motor.

So I'll pay the net $100 a year in additional energy cost and never have
to worry about my PSC motor failing me for several decades - if ever.

Even after gov't rebates, forking out a minimum $2000 for a new furnace
is going to take years to recover that, with the ECM motor delivering
just $100 a year and the burners / heat-exchanger *maybe* giving me an
additional $200 a year in savings. *And by the time I've made those
savings the furnace will be near the end of it's reliable life-span.

So your saying that the "reliable life span" of the new furnaces is only 6 -
7 years?? This may be true when installed by John Q Homeowner, or the lowest
bidder, however when correctly installed, properly adjusted, and with
correctly sized ductwork, the normal lifespan is 20 - 23 years.

You still cannot buy a new furnace today that *DOESN"T* have electronics
controling it. Furnaces with PSC motors are still available, but only in the
cheapest, lowest efficiency, "builder grade" models.


I don't know what you consider "cheapest, lowest efficiency", but I'm
looking at
quotes for a Rheem 120K BTU, 95% efficient furnace that meets the govt
high
efficiency standards for the tax credit. And it has a single speed
PSC motor.
Can also get the same furnace and AC system from Trane, for $800
more.

While I don't agree with Home Guy on everything, I do agree that in
many cases
the extra cost of models with an ECM blower aren't worth it. That's
from two standpoints.
First is that those models only save on the blower electricity. And
then independent
studies have shown that you get the 40% electricity savings if the
duct work is ideal.
If it's good, you get like 25%. If it's typical it's more like 15
-20%. And if it's poor
ducting, you get 10% to -10%. So, for maybe a 15-20% savings, you
have a significantly
higher initial outlay, plus exposure to higher repair costs if the
blower motor or it's added
drive electronics fails.

I can see going with the variable ECM motor if you want to run the
blower 24/7. Or if you
highly value that it starts up quietly, can run at low speed longer to
even out heat better with
a two stage furnace on mild heating days. Or can run on slow speed
with AC to dehumidify better.
But none of those are that important to me.






Maybe thats why your so against the new furnaces... your got the cheapest
POS furnace you could find, you got what you paid for, and now your not
happy with it.- Hide quoted text -

- Show quoted text -