In the Polaris pool cleaner thread the subject of variable speed
pool pumps came up. Which got me thinking about them
again because a friend who has a pool with a single speed
pump is considering options. Doing a bit of research, here's
what I have concluded and I wanted to see if anyone has
addional thoughts.

First, it looks like because of the design of the variable speed
permanent magnet motors, they are inherently more efficient
so you use about 15-20% less energy even at full speed.

Second, the biggest savings in energy come from slowing
the pump down, reducing the flow resistance. That means
you can run the pump for say 4 times as long, at 1/4 the
flow rate, move the same amount of water, but save 70 to
80% or so in energy.

However, the price of these pumps is very high. A complete
new pump runs from $900 to $1200 dollars online. The next
obvious problem is that they typically have only a 1 yr
warranty. I found an online story where a guy bought
a Pentair Intelliflow one where one of the two small control
boards failed shortly after the warranty ended. He says
Pentair will not sell the replacement board as a seperate
part or take pumps back for repair. He would have to buy
a whole new pump. It looks like Jandy, another major
manufacturer, does sell parts, but the equiv part for their
pump would be $400.

So, this got me to thinking. It appears to me the biggest
part of the energy savings can be obtained by just going
to a dual speed pump. And since my friend has a working
pump that is about 5 years old, I'm thinking the most
cost effective solution is to just replace the motor with
a dual speed motor. We could do that for under $300.

With the variable speed pump, assuming we bought the
lowest cost one, by my calcs, with the energy savings
it would take almost 4 years
to break even. With the dual speed motor, it would take
less than 2 years. The pool is seasonal, used 3.5 months
a year. And it looks to me like the additional savings in
energy going with the true variable speed pump is only
about $50 more a year over the dual speed. And then
what happens if the fancy electronics on this motor,
which sits outside all year, fails at say year 3, 5 etc?

The only other advantage of the variable is you can fine
tune it to run at exactly the speed you want, but I don't
see a compelling need for that. Also, there aren't any
utility rebates available here that would alter the
equation. So, it seems for this app, the variable speed
makes no sense. If you had a pool running year round,
higher cost electric, rebates, etc, then the results
might be different.

So, swap out the motor for the dual speed for $300? Any other
thoughts, issues I missed?

On Apr 22, 8:16*am, "
wrote:
In the Polaris pool cleaner thread the subject of variable speed
pool pumps came up. * Which got me thinking about them
again because a friend who has a pool with a single speed
pump is considering options. Doing a bit of research, here's
*what I have concluded and I wanted to see if anyone has
*addional thoughts.

First, it looks like because of the design of the variable speed
permanent magnet motors, they are inherently more efficient
so you use about 15-20% less energy even at full speed.

Second, the biggest savings in energy come from slowing
the pump down, reducing the flow resistance. *That means
you can run the pump for say 4 times as long, at 1/4 the
flow rate, move the same amount of water, but save 70 to
80% or so in energy.

However, the price of these pumps is very high. *A complete
new pump runs from $900 to $1200 dollars online. *The next
obvious problem is that they typically have only a 1 yr
warranty. * I found an online story where a guy bought
a Pentair Intelliflow one where one of the two small control
boards failed shortly after the warranty ended. *He says
Pentair will not sell the replacement board as a seperate
part or take pumps back for repair. *He would have to buy
a whole new pump. * It looks like Jandy, another major
manufacturer, does sell parts, but the equiv part for their
pump would be $400.

So, this got me to thinking. *It appears to me the biggest
part of the energy savings can be obtained by just going
to a dual speed pump. * And since my friend has a working
pump that is about 5 years old, I'm thinking the most
cost effective solution is to just replace the motor with
a dual speed motor. *We could do that for under $300.

With the variable speed pump, assuming we bought the
lowest cost one, by my calcs, with the energy savings
*it would take almost 4 years
to break even. * With the dual speed motor, it would take
less than 2 years. *The pool is seasonal, used 3.5 months
a year. * And it looks to me like the additional savings in
energy going with the true variable speed pump is only
about $50 more a year over the dual speed. *And then
what happens if the fancy electronics on this motor,
which sits outside all year, fails at say year 3, 5 etc?

The only other advantage of the variable is you can fine
tune it to run at exactly the speed you want, but I don't
see a compelling need for that. *Also, there aren't any
utility rebates available here that would alter the
equation. * So, it seems for this app, the variable speed
makes no sense. * If you had a pool running year round,
higher cost electric, rebates, etc, then the results
might be different.

So, swap out the motor for the dual speed for $300? *Any other
thoughts, issues I missed?

T4-

Looks to me like you covered all the issues..... dual speed is right
choice.
Fancy electronics (unless cheap to replace) will eat up any energy
cost savings when the board fails.

cheers
Bob

On Apr 22, 11:42*am, DD_BobK wrote:
On Apr 22, 8:16*am, "
wrote:





In the Polaris pool cleaner thread the subject of variable speed
pool pumps came up. * Which got me thinking about them
again because a friend who has a pool with a single speed
pump is considering options. Doing a bit of research, here's
*what I have concluded and I wanted to see if anyone has
*addional thoughts.

First, it looks like because of the design of the variable speed
permanent magnet motors, they are inherently more efficient
so you use about 15-20% less energy even at full speed.

Second, the biggest savings in energy come from slowing
the pump down, reducing the flow resistance. *That means
you can run the pump for say 4 times as long, at 1/4 the
flow rate, move the same amount of water, but save 70 to
80% or so in energy.

However, the price of these pumps is very high. *A complete
new pump runs from $900 to $1200 dollars online. *The next
obvious problem is that they typically have only a 1 yr
warranty. * I found an online story where a guy bought
a Pentair Intelliflow one where one of the two small control
boards failed shortly after the warranty ended. *He says
Pentair will not sell the replacement board as a seperate
part or take pumps back for repair. *He would have to buy
a whole new pump. * It looks like Jandy, another major
manufacturer, does sell parts, but the equiv part for their
pump would be $400.

So, this got me to thinking. *It appears to me the biggest
part of the energy savings can be obtained by just going
to a dual speed pump. * And since my friend has a working
pump that is about 5 years old, I'm thinking the most
cost effective solution is to just replace the motor with
a dual speed motor. *We could do that for under $300.

With the variable speed pump, assuming we bought the
lowest cost one, by my calcs, with the energy savings
*it would take almost 4 years
to break even. * With the dual speed motor, it would take
less than 2 years. *The pool is seasonal, used 3.5 months
a year. * And it looks to me like the additional savings in
energy going with the true variable speed pump is only
about $50 more a year over the dual speed. *And then
what happens if the fancy electronics on this motor,
which sits outside all year, fails at say year 3, 5 etc?

The only other advantage of the variable is you can fine
tune it to run at exactly the speed you want, but I don't
see a compelling need for that. *Also, there aren't any
utility rebates available here that would alter the
equation. * So, it seems for this app, the variable speed
makes no sense. * If you had a pool running year round,
higher cost electric, rebates, etc, then the results
might be different.

So, swap out the motor for the dual speed for $300? *Any other
thoughts, issues I missed?

T4-

Looks to me like you covered all the issues..... *dual speed is right
choice.
Fancy electronics (unless cheap to replace) will eat up any energy
cost savings when the board fails. *

cheers
Bob- Hide quoted text -

- Show quoted text -

I don't have a pool, but the OP seems to have his ducks right in line.

On Apr 22, 9:08*am, wrote:
On Fri, 22 Apr 2011 08:16:36 -0700 (PDT), "









wrote:
In the Polaris pool cleaner thread the subject of variable speed
pool pumps came up. * Which got me thinking about them
again because a friend who has a pool with a single speed
pump is considering options. Doing a bit of research, here's
what I have concluded and I wanted to see if anyone has
addional thoughts.

First, it looks like because of the design of the variable speed
permanent magnet motors, they are inherently more efficient
so you use about 15-20% less energy even at full speed.

Second, the biggest savings in energy come from slowing
the pump down, reducing the flow resistance. *That means
you can run the pump for say 4 times as long, at 1/4 the
flow rate, move the same amount of water, but save 70 to
80% or so in energy.

However, the price of these pumps is very high. *A complete
new pump runs from $900 to $1200 dollars online. *The next
obvious problem is that they typically have only a 1 yr
warranty. * I found an online story where a guy bought
a Pentair Intelliflow one where one of the two small control
boards failed shortly after the warranty ended. *He says
Pentair will not sell the replacement board as a seperate
part or take pumps back for repair. *He would have to buy
a whole new pump. * It looks like Jandy, another major
manufacturer, does sell parts, but the equiv part for their
pump would be $400.

So, this got me to thinking. *It appears to me the biggest
part of the energy savings can be obtained by just going
to a dual speed pump. * And since my friend has a working
pump that is about 5 years old, I'm thinking the most
cost effective solution is to just replace the motor with
a dual speed motor. *We could do that for under $300.

With the variable speed pump, assuming we bought the
lowest cost one, by my calcs, with the energy savings
it would take almost 4 years
to break even. * With the dual speed motor, it would take
less than 2 years. *The pool is seasonal, used 3.5 months
a year. * And it looks to me like the additional savings in
energy going with the true variable speed pump is only
about $50 more a year over the dual speed. *And then
what happens if the fancy electronics on this motor,
which sits outside all year, fails at say year 3, 5 etc?

The only other advantage of the variable is you can fine
tune it to run at exactly the speed you want, but I don't
see a compelling need for that. *Also, there aren't any
utility rebates available here that would alter the
equation. * So, it seems for this app, the variable speed
makes no sense. * If you had a pool running year round,
higher cost electric, rebates, etc, then the results
might be different.

So, swap out the motor for the dual speed for $300? *Any other
thoughts, issues I missed?

This still does not make sense to me and it has become law in a lot of
places.
If you can really keep your pool clean with a 1/4th hp pump, why not
just buy a 1/4th hp pump?
I run my 1HP on a timer that assures one turn over a day and runs
strong enough to vacuum at the same time. I am not sure how a variable
speed pump would save me a dime.

You can probably 95% of the time get by at 25% power (low speed
running)

BUT there might be sometimes when you need full system flow.

In SoCal we have seasonal winds that can super load a pool with dirt,
leaves & other debris.
To clean the pool up quickly, it might take a couple days running
24hrs at full RPM.
At low speed it would take a lot longer.

But for "typical" / "low dirt load" many hours at low speed could do
the job.

Two speed pumps give you enough flexibility to tailor motor speed to
pool cleaning requirements.

Kinda goes along with the concept of "side stream" / "kidney loop"
filtering of a hydraulic oil tank as opposed to full flow filtering.

It's all about the total energy used to accomplish the job.

At first glance dual speed pumps might seem silly but they do the job
AND save money.

cheers
Bob

On Apr 22, 12:51*pm, DD_BobK wrote:
On Apr 22, 9:08*am, wrote:





On Fri, 22 Apr 2011 08:16:36 -0700 (PDT), "

wrote:
In the Polaris pool cleaner thread the subject of variable speed
pool pumps came up. * Which got me thinking about them
again because a friend who has a pool with a single speed
pump is considering options. Doing a bit of research, here's
what I have concluded and I wanted to see if anyone has
addional thoughts.

First, it looks like because of the design of the variable speed
permanent magnet motors, they are inherently more efficient
so you use about 15-20% less energy even at full speed.

Second, the biggest savings in energy come from slowing
the pump down, reducing the flow resistance. *That means
you can run the pump for say 4 times as long, at 1/4 the
flow rate, move the same amount of water, but save 70 to
80% or so in energy.

However, the price of these pumps is very high. *A complete
new pump runs from $900 to $1200 dollars online. *The next
obvious problem is that they typically have only a 1 yr
warranty. * I found an online story where a guy bought
a Pentair Intelliflow one where one of the two small control
boards failed shortly after the warranty ended. *He says
Pentair will not sell the replacement board as a seperate
part or take pumps back for repair. *He would have to buy
a whole new pump. * It looks like Jandy, another major
manufacturer, does sell parts, but the equiv part for their
pump would be $400.

So, this got me to thinking. *It appears to me the biggest
part of the energy savings can be obtained by just going
to a dual speed pump. * And since my friend has a working
pump that is about 5 years old, I'm thinking the most
cost effective solution is to just replace the motor with
a dual speed motor. *We could do that for under $300.

With the variable speed pump, assuming we bought the
lowest cost one, by my calcs, with the energy savings
it would take almost 4 years
to break even. * With the dual speed motor, it would take
less than 2 years. *The pool is seasonal, used 3.5 months
a year. * And it looks to me like the additional savings in
energy going with the true variable speed pump is only
about $50 more a year over the dual speed. *And then
what happens if the fancy electronics on this motor,
which sits outside all year, fails at say year 3, 5 etc?

The only other advantage of the variable is you can fine
tune it to run at exactly the speed you want, but I don't
see a compelling need for that. *Also, there aren't any
utility rebates available here that would alter the
equation. * So, it seems for this app, the variable speed
makes no sense. * If you had a pool running year round,
higher cost electric, rebates, etc, then the results
might be different.

So, swap out the motor for the dual speed for $300? *Any other
thoughts, issues I missed?

This still does not make sense to me and it has become law in a lot of
places.
If you can really keep your pool clean with a 1/4th hp pump, why not
just buy a 1/4th hp pump?
I run my 1HP on a timer that assures one turn over a day and runs
strong enough to vacuum at the same time. I am not sure how a variable
speed pump would save me a dime.

You can probably 95% of the time get by at 25% power (low speed
running)

BUT there might be sometimes when you need full system flow.

In SoCal we have seasonal winds that can super load a pool with dirt,
leaves & other debris.
To clean the pool up quickly, it might take a couple days running
24hrs at full RPM.
At low speed it would take a lot longer. *

But for "typical" / "low dirt load" many hours at low speed could do
the job.

Agree with the advantage to full speed if the pool has some
problem, eg it's startup after winter or it's dirty and you have
a pool party this afternoon, etc.

The higher speed would probably be needed to backwash the
DE filter. Doubt that low speed would do the job. And also
if the pool gets too full from rain and you want to lower it
would be better to get it done in 20 mins instead of an hour.
But overall, I think the backwashing is the one thing I don't
think you can get around. Plus a dual speed motor is only
$100 more than single.








Two speed pumps give you enough flexibility to tailor motor speed to
pool cleaning requirements.

Kinda goes along with the concept of *"side stream" / "kidney loop"
filtering of a hydraulic oil tank as opposed to full flow filtering.

It's all about the total energy used to accomplish the job.

At first glance dual speed pumps might seem silly but they do the job
AND save money.

cheers
Bob- Hide quoted text -

- Show quoted text -

On Apr 22, 4:16*pm, "
wrote:
In the Polaris pool cleaner thread the subject of variable speed
pool pumps came up. * Which got me thinking about them
again because a friend who has a pool with a single speed
pump is considering options. Doing a bit of research, here's
*what I have concluded and I wanted to see if anyone has
*addional thoughts.

First, it looks like because of the design of the variable speed
permanent magnet motors, they are inherently more efficient
so you use about 15-20% less energy even at full speed.

Second, the biggest savings in energy come from slowing
the pump down, reducing the flow resistance. *That means
you can run the pump for say 4 times as long, at 1/4 the
flow rate, move the same amount of water, but save 70 to
80% or so in energy.

However, the price of these pumps is very high. *A complete
new pump runs from $900 to $1200 dollars online. *The next
obvious problem is that they typically have only a 1 yr
warranty. * I found an online story where a guy bought
a Pentair Intelliflow one where one of the two small control
boards failed shortly after the warranty ended. *He says
Pentair will not sell the replacement board as a seperate
part or take pumps back for repair. *He would have to buy
a whole new pump. * It looks like Jandy, another major
manufacturer, does sell parts, but the equiv part for their
pump would be $400.

So, this got me to thinking. *It appears to me the biggest
part of the energy savings can be obtained by just going
to a dual speed pump. * And since my friend has a working
pump that is about 5 years old, I'm thinking the most
cost effective solution is to just replace the motor with
a dual speed motor. *We could do that for under $300.

With the variable speed pump, assuming we bought the
lowest cost one, by my calcs, with the energy savings
*it would take almost 4 years
to break even. * With the dual speed motor, it would take
less than 2 years. *The pool is seasonal, used 3.5 months
a year. * And it looks to me like the additional savings in
energy going with the true variable speed pump is only
about $50 more a year over the dual speed. *And then
what happens if the fancy electronics on this motor,
which sits outside all year, fails at say year 3, 5 etc?

The only other advantage of the variable is you can fine
tune it to run at exactly the speed you want, but I don't
see a compelling need for that. *Also, there aren't any
utility rebates available here that would alter the
equation. * So, it seems for this app, the variable speed
makes no sense. * If you had a pool running year round,
higher cost electric, rebates, etc, then the results
might be different.

So, swap out the motor for the dual speed for $300? *Any other
thoughts, issues I missed?

The water quality in your pool varies with usage. So in times of low
useage, there is ample scope for running the pump slower and saving
electricity.
You will also save heating costs if the pool is heated.
Hit the high speed when the pool is in use and for a couple of hours
afterwards..
If things are OK if the pump is off for a time even better.
A floating pool cover is a good investment too, saves heating,
cleaning, water and chemicals.
A suspended one is less good.

On 4/22/2011 1:05 PM, harry wrote:
On Apr 22, 4:16 pm,
wrote:
In the Polaris pool cleaner thread the subject of variable speed
pool pumps came up. Which got me thinking about them
again because a friend who has a pool with a single speed
pump is considering options. Doing a bit of research, here's
what I have concluded and I wanted to see if anyone has
addional thoughts.

First, it looks like because of the design of the variable speed
permanent magnet motors, they are inherently more efficient
so you use about 15-20% less energy even at full speed.

Second, the biggest savings in energy come from slowing
the pump down, reducing the flow resistance. That means
you can run the pump for say 4 times as long, at 1/4 the
flow rate, move the same amount of water, but save 70 to
80% or so in energy.

However, the price of these pumps is very high. A complete
new pump runs from $900 to $1200 dollars online. The next
obvious problem is that they typically have only a 1 yr
warranty. I found an online story where a guy bought
a Pentair Intelliflow one where one of the two small control
boards failed shortly after the warranty ended. He says
Pentair will not sell the replacement board as a seperate
part or take pumps back for repair. He would have to buy
a whole new pump. It looks like Jandy, another major
manufacturer, does sell parts, but the equiv part for their
pump would be $400.

So, this got me to thinking. It appears to me the biggest
part of the energy savings can be obtained by just going
to a dual speed pump. And since my friend has a working
pump that is about 5 years old, I'm thinking the most
cost effective solution is to just replace the motor with
a dual speed motor. We could do that for under $300.

With the variable speed pump, assuming we bought the
lowest cost one, by my calcs, with the energy savings
it would take almost 4 years
to break even. With the dual speed motor, it would take
less than 2 years. The pool is seasonal, used 3.5 months
a year. And it looks to me like the additional savings in
energy going with the true variable speed pump is only
about $50 more a year over the dual speed. And then
what happens if the fancy electronics on this motor,
which sits outside all year, fails at say year 3, 5 etc?

The only other advantage of the variable is you can fine
tune it to run at exactly the speed you want, but I don't
see a compelling need for that. Also, there aren't any
utility rebates available here that would alter the
equation. So, it seems for this app, the variable speed
makes no sense. If you had a pool running year round,
higher cost electric, rebates, etc, then the results
might be different.

So, swap out the motor for the dual speed for $300? Any other
thoughts, issues I missed?

The water quality in your pool varies with usage. So in times of low
useage, there is ample scope for running the pump slower and saving
electricity.
You will also save heating costs if the pool is heated.
Hit the high speed when the pool is in use and for a couple of hours
afterwards..
If things are OK if the pump is off for a time even better.
A floating pool cover is a good investment too, saves heating,
cleaning, water and chemicals.
A suspended one is less good.



I just don't see the savings. Run the pool less at high speed or run the
pool more at low speed? What's the difference? A more expensive pump? If
it runs more efficient at high speed I can see it otherwise it sounds
like smoke and mirrors.

Jim

JimT wrote:
On 4/22/2011 1:05 PM, harry wrote:
On Apr 22, 4:16 pm,
wrote:
In the Polaris pool cleaner thread the subject of variable speed
pool pumps came up. Which got me thinking about them
again because a friend who has a pool with a single speed
pump is considering options. Doing a bit of research, here's
what I have concluded and I wanted to see if anyone has
addional thoughts.

First, it looks like because of the design of the variable speed
permanent magnet motors, they are inherently more efficient
so you use about 15-20% less energy even at full speed.

Second, the biggest savings in energy come from slowing
the pump down, reducing the flow resistance. That means
you can run the pump for say 4 times as long, at 1/4 the
flow rate, move the same amount of water, but save 70 to
80% or so in energy.

However, the price of these pumps is very high. A complete
new pump runs from $900 to $1200 dollars online. The next
obvious problem is that they typically have only a 1 yr
warranty. I found an online story where a guy bought
a Pentair Intelliflow one where one of the two small control
boards failed shortly after the warranty ended. He says
Pentair will not sell the replacement board as a seperate
part or take pumps back for repair. He would have to buy
a whole new pump. It looks like Jandy, another major
manufacturer, does sell parts, but the equiv part for their
pump would be $400.

So, this got me to thinking. It appears to me the biggest
part of the energy savings can be obtained by just going
to a dual speed pump. And since my friend has a working
pump that is about 5 years old, I'm thinking the most
cost effective solution is to just replace the motor with
a dual speed motor. We could do that for under $300.

With the variable speed pump, assuming we bought the
lowest cost one, by my calcs, with the energy savings
it would take almost 4 years
to break even. With the dual speed motor, it would take
less than 2 years. The pool is seasonal, used 3.5 months
a year. And it looks to me like the additional savings in
energy going with the true variable speed pump is only
about $50 more a year over the dual speed. And then
what happens if the fancy electronics on this motor,
which sits outside all year, fails at say year 3, 5 etc?

The only other advantage of the variable is you can fine
tune it to run at exactly the speed you want, but I don't
see a compelling need for that. Also, there aren't any
utility rebates available here that would alter the
equation. So, it seems for this app, the variable speed
makes no sense. If you had a pool running year round,
higher cost electric, rebates, etc, then the results
might be different.

So, swap out the motor for the dual speed for $300? Any other
thoughts, issues I missed?

The water quality in your pool varies with usage. So in times of low
useage, there is ample scope for running the pump slower and saving
electricity.
You will also save heating costs if the pool is heated.
Hit the high speed when the pool is in use and for a couple of hours
afterwards..
If things are OK if the pump is off for a time even better.
A floating pool cover is a good investment too, saves heating,
cleaning, water and chemicals.
A suspended one is less good.



I just don't see the savings. Run the pool less at high speed or run
the pool more at low speed? What's the difference? A more expensive
pump? If it runs more efficient at high speed I can see it otherwise
it sounds like smoke and mirrors.


Low speed produces less back pressure, therefore uses less power/volume pumped.
It is just more efficient. Kind of like driving 55 is more efficient than
driving 100.

On 4/22/2011 5:13 PM, Bob F wrote:
JimT wrote:
On 4/22/2011 1:05 PM, harry wrote:
On Apr 22, 4:16 pm,
wrote:
In the Polaris pool cleaner thread the subject of variable speed
pool pumps came up. Which got me thinking about them
again because a friend who has a pool with a single speed
pump is considering options. Doing a bit of research, here's
what I have concluded and I wanted to see if anyone has
addional thoughts.

First, it looks like because of the design of the variable speed
permanent magnet motors, they are inherently more efficient
so you use about 15-20% less energy even at full speed.

Second, the biggest savings in energy come from slowing
the pump down, reducing the flow resistance. That means
you can run the pump for say 4 times as long, at 1/4 the
flow rate, move the same amount of water, but save 70 to
80% or so in energy.

However, the price of these pumps is very high. A complete
new pump runs from $900 to $1200 dollars online. The next
obvious problem is that they typically have only a 1 yr
warranty. I found an online story where a guy bought
a Pentair Intelliflow one where one of the two small control
boards failed shortly after the warranty ended. He says
Pentair will not sell the replacement board as a seperate
part or take pumps back for repair. He would have to buy
a whole new pump. It looks like Jandy, another major
manufacturer, does sell parts, but the equiv part for their
pump would be $400.

So, this got me to thinking. It appears to me the biggest
part of the energy savings can be obtained by just going
to a dual speed pump. And since my friend has a working
pump that is about 5 years old, I'm thinking the most
cost effective solution is to just replace the motor with
a dual speed motor. We could do that for under $300.

With the variable speed pump, assuming we bought the
lowest cost one, by my calcs, with the energy savings
it would take almost 4 years
to break even. With the dual speed motor, it would take
less than 2 years. The pool is seasonal, used 3.5 months
a year. And it looks to me like the additional savings in
energy going with the true variable speed pump is only
about $50 more a year over the dual speed. And then
what happens if the fancy electronics on this motor,
which sits outside all year, fails at say year 3, 5 etc?

The only other advantage of the variable is you can fine
tune it to run at exactly the speed you want, but I don't
see a compelling need for that. Also, there aren't any
utility rebates available here that would alter the
equation. So, it seems for this app, the variable speed
makes no sense. If you had a pool running year round,
higher cost electric, rebates, etc, then the results
might be different.

So, swap out the motor for the dual speed for $300? Any other
thoughts, issues I missed?

The water quality in your pool varies with usage. So in times of low
useage, there is ample scope for running the pump slower and saving
electricity.
You will also save heating costs if the pool is heated.
Hit the high speed when the pool is in use and for a couple of hours
afterwards..
If things are OK if the pump is off for a time even better.
A floating pool cover is a good investment too, saves heating,
cleaning, water and chemicals.
A suspended one is less good.



I just don't see the savings. Run the pool less at high speed or run
the pool more at low speed? What's the difference? A more expensive
pump? If it runs more efficient at high speed I can see it otherwise
it sounds like smoke and mirrors.


Low speed produces less back pressure, therefore uses less power/volume pumped.
It is just more efficient. Kind of like driving 55 is more efficient than
driving 100.



Well if you put it like that. :-)

Here's a video that explains it well.

http://tinyurl.com/3buqwfl

Next time I might look into a var speed pump.

Jim

On Fri, 22 Apr 2011 08:16:36 -0700 (PDT), "
wrote:

In the Polaris pool cleaner thread the subject of variable speed
pool pumps came up. Which got me thinking about them
again because a friend who has a pool with a single speed
pump is considering options. Doing a bit of research, here's
what I have concluded and I wanted to see if anyone has
addional thoughts.

First, it looks like because of the design of the variable speed
permanent magnet motors, they are inherently more efficient
so you use about 15-20% less energy even at full speed.

Second, the biggest savings in energy come from slowing
the pump down, reducing the flow resistance. That means
you can run the pump for say 4 times as long, at 1/4 the
flow rate, move the same amount of water, but save 70 to
80% or so in energy.

However, the price of these pumps is very high. A complete
new pump runs from $900 to $1200 dollars online. The next
obvious problem is that they typically have only a 1 yr
warranty. I found an online story where a guy bought
a Pentair Intelliflow one where one of the two small control
boards failed shortly after the warranty ended. He says
Pentair will not sell the replacement board as a seperate
part or take pumps back for repair. He would have to buy
a whole new pump. It looks like Jandy, another major
manufacturer, does sell parts, but the equiv part for their
pump would be $400.

So, this got me to thinking. It appears to me the biggest
part of the energy savings can be obtained by just going
to a dual speed pump. And since my friend has a working
pump that is about 5 years old, I'm thinking the most
cost effective solution is to just replace the motor with
a dual speed motor. We could do that for under $300.

With the variable speed pump, assuming we bought the
lowest cost one, by my calcs, with the energy savings
it would take almost 4 years
to break even. With the dual speed motor, it would take
less than 2 years. The pool is seasonal, used 3.5 months
a year. And it looks to me like the additional savings in
energy going with the true variable speed pump is only
about $50 more a year over the dual speed. And then
what happens if the fancy electronics on this motor,
which sits outside all year, fails at say year 3, 5 etc?

The only other advantage of the variable is you can fine
tune it to run at exactly the speed you want, but I don't
see a compelling need for that. Also, there aren't any
utility rebates available here that would alter the
equation. So, it seems for this app, the variable speed
makes no sense. If you had a pool running year round,
higher cost electric, rebates, etc, then the results
might be different.

So, swap out the motor for the dual speed for $300? Any other
thoughts, issues I missed?


I looked at the same issue a few months ago. I need to have the pump
run at high speed at least part of the time in order for my sweep
system to work. To do that the least expensive option would be a 2
speed motor installed on my current pump. But to automate it I also
would need to buy the dual timer control for it which is another $100.
By the time you add it all up it will take several years to break
even. So I'm still on the fence. My current pump and motor is 20+
years old and when it goes out I will think about this issue again.

On Apr 23, 2:23*am, Ashton Crusher wrote:
On Fri, 22 Apr 2011 08:16:36 -0700 (PDT), "





wrote:
In the Polaris pool cleaner thread the subject of variable speed
pool pumps came up. * Which got me thinking about them
again because a friend who has a pool with a single speed
pump is considering options. Doing a bit of research, here's
what I have concluded and I wanted to see if anyone has
addional thoughts.

First, it looks like because of the design of the variable speed
permanent magnet motors, they are inherently more efficient
so you use about 15-20% less energy even at full speed.

Second, the biggest savings in energy come from slowing
the pump down, reducing the flow resistance. *That means
you can run the pump for say 4 times as long, at 1/4 the
flow rate, move the same amount of water, but save 70 to
80% or so in energy.

However, the price of these pumps is very high. *A complete
new pump runs from $900 to $1200 dollars online. *The next
obvious problem is that they typically have only a 1 yr
warranty. * I found an online story where a guy bought
a Pentair Intelliflow one where one of the two small control
boards failed shortly after the warranty ended. *He says
Pentair will not sell the replacement board as a seperate
part or take pumps back for repair. *He would have to buy
a whole new pump. * It looks like Jandy, another major
manufacturer, does sell parts, but the equiv part for their
pump would be $400.

So, this got me to thinking. *It appears to me the biggest
part of the energy savings can be obtained by just going
to a dual speed pump. * And since my friend has a working
pump that is about 5 years old, I'm thinking the most
cost effective solution is to just replace the motor with
a dual speed motor. *We could do that for under $300.

With the variable speed pump, assuming we bought the
lowest cost one, by my calcs, with the energy savings
it would take almost 4 years
to break even. * With the dual speed motor, it would take
less than 2 years. *The pool is seasonal, used 3.5 months
a year. * And it looks to me like the additional savings in
energy going with the true variable speed pump is only
about $50 more a year over the dual speed. *And then
what happens if the fancy electronics on this motor,
which sits outside all year, fails at say year 3, 5 etc?

The only other advantage of the variable is you can fine
tune it to run at exactly the speed you want, but I don't
see a compelling need for that. *Also, there aren't any
utility rebates available here that would alter the
equation. * So, it seems for this app, the variable speed
makes no sense. * If you had a pool running year round,
higher cost electric, rebates, etc, then the results
might be different.

So, swap out the motor for the dual speed for $300? *Any other
thoughts, issues I missed?

I looked at the same issue a few months ago. *I need to have the pump
run at high speed at least part of the time in order for my sweep
system to work. *To do that the least expensive option would be a 2
speed motor installed on my current pump. *But to automate it I also
would need to buy the dual timer control for it which is another $100.
By the time you add it all up it will take several years to break
even. *So I'm still on the fence. *My current pump and motor is 20+
years old and when it goes out I will think about this issue again.

YOU'RE A. C. YOU DON'T HAVE TO TOIL WITH THAT.
IMPORT A TECH FROM AN AMERICAN GHETTO TECH TEAM FOR A FULL SERVICE
UPGRADE.
THEY CAN USE THE GREEN TIME (-;
PAT ECUM

On Apr 23, 2:57*am, The Ghost in The Machine
wrote:
On Apr 23, 2:23*am, Ashton Crusher wrote:





On Fri, 22 Apr 2011 08:16:36 -0700 (PDT), "

wrote:
In the Polaris pool cleaner thread the subject of variable speed
pool pumps came up. * Which got me thinking about them
again because a friend who has a pool with a single speed
pump is considering options. Doing a bit of research, here's
what I have concluded and I wanted to see if anyone has
addional thoughts.

First, it looks like because of the design of the variable speed
permanent magnet motors, they are inherently more efficient
so you use about 15-20% less energy even at full speed.

Second, the biggest savings in energy come from slowing
the pump down, reducing the flow resistance. *That means
you can run the pump for say 4 times as long, at 1/4 the
flow rate, move the same amount of water, but save 70 to
80% or so in energy.

However, the price of these pumps is very high. *A complete
new pump runs from $900 to $1200 dollars online. *The next
obvious problem is that they typically have only a 1 yr
warranty. * I found an online story where a guy bought
a Pentair Intelliflow one where one of the two small control
boards failed shortly after the warranty ended. *He says
Pentair will not sell the replacement board as a seperate
part or take pumps back for repair. *He would have to buy
a whole new pump. * It looks like Jandy, another major
manufacturer, does sell parts, but the equiv part for their
pump would be $400.

So, this got me to thinking. *It appears to me the biggest
part of the energy savings can be obtained by just going
to a dual speed pump. * And since my friend has a working
pump that is about 5 years old, I'm thinking the most
cost effective solution is to just replace the motor with
a dual speed motor. *We could do that for under $300.

With the variable speed pump, assuming we bought the
lowest cost one, by my calcs, with the energy savings
it would take almost 4 years
to break even. * With the dual speed motor, it would take
less than 2 years. *The pool is seasonal, used 3.5 months
a year. * And it looks to me like the additional savings in
energy going with the true variable speed pump is only
about $50 more a year over the dual speed. *And then
what happens if the fancy electronics on this motor,
which sits outside all year, fails at say year 3, 5 etc?

The only other advantage of the variable is you can fine
tune it to run at exactly the speed you want, but I don't
see a compelling need for that. *Also, there aren't any
utility rebates available here that would alter the
equation. * So, it seems for this app, the variable speed
makes no sense. * If you had a pool running year round,
higher cost electric, rebates, etc, then the results
might be different.

So, swap out the motor for the dual speed for $300? *Any other
thoughts, issues I missed?

I looked at the same issue a few months ago. *I need to have the pump
run at high speed at least part of the time in order for my sweep
system to work. *To do that the least expensive option would be a 2
speed motor installed on my current pump. *But to automate it I also
would need to buy the dual timer control for it which is another $100.
By the time you add it all up it will take several years to break
even. *So I'm still on the fence. *My current pump and motor is 20+
years old and when it goes out I will think about this issue again.

YOU'RE A. C. YOU DON'T HAVE TO TOIL WITH THAT.
IMPORT A TECH FROM AN AMERICAN GHETTO TECH TEAM FOR A FULL SERVICE
UPGRADE.
THEY CAN USE THE GREEN TIME (-;
PAT ECUM

WHO KNOWS YOU'LL HELP THE ECONOMY & ThEY MAY CREATE "POOLS R U" : )

No? Ok, more styled?....."PUWLZ R U" ( ;

PAT ECUM
(RESPOND HERE, SO, TO OPEN MY [NET DRIVE] INBOX FOR YOU)

On Apr 22, 10:10*pm, wrote:
On Fri, 22 Apr 2011 09:51:55 -0700 (PDT), DD_BobK
wrote:





On Apr 22, 9:08*am, wrote:
On Fri, 22 Apr 2011 08:16:36 -0700 (PDT), "

wrote:
In the Polaris pool cleaner thread the subject of variable speed
pool pumps came up. * Which got me thinking about them
again because a friend who has a pool with a single speed
pump is considering options. Doing a bit of research, here's
what I have concluded and I wanted to see if anyone has
addional thoughts.

First, it looks like because of the design of the variable speed
permanent magnet motors, they are inherently more efficient
so you use about 15-20% less energy even at full speed.

Second, the biggest savings in energy come from slowing
the pump down, reducing the flow resistance. *That means
you can run the pump for say 4 times as long, at 1/4 the
flow rate, move the same amount of water, but save 70 to
80% or so in energy.

However, the price of these pumps is very high. *A complete
new pump runs from $900 to $1200 dollars online. *The next
obvious problem is that they typically have only a 1 yr
warranty. * I found an online story where a guy bought
a Pentair Intelliflow one where one of the two small control
boards failed shortly after the warranty ended. *He says
Pentair will not sell the replacement board as a seperate
part or take pumps back for repair. *He would have to buy
a whole new pump. * It looks like Jandy, another major
manufacturer, does sell parts, but the equiv part for their
pump would be $400.

So, this got me to thinking. *It appears to me the biggest
part of the energy savings can be obtained by just going
to a dual speed pump. * And since my friend has a working
pump that is about 5 years old, I'm thinking the most
cost effective solution is to just replace the motor with
a dual speed motor. *We could do that for under $300.

With the variable speed pump, assuming we bought the
lowest cost one, by my calcs, with the energy savings
it would take almost 4 years
to break even. * With the dual speed motor, it would take
less than 2 years. *The pool is seasonal, used 3.5 months
a year. * And it looks to me like the additional savings in
energy going with the true variable speed pump is only
about $50 more a year over the dual speed. *And then
what happens if the fancy electronics on this motor,
which sits outside all year, fails at say year 3, 5 etc?

The only other advantage of the variable is you can fine
tune it to run at exactly the speed you want, but I don't
see a compelling need for that. *Also, there aren't any
utility rebates available here that would alter the
equation. * So, it seems for this app, the variable speed
makes no sense. * If you had a pool running year round,
higher cost electric, rebates, etc, then the results
might be different.

So, swap out the motor for the dual speed for $300? *Any other
thoughts, issues I missed?

This still does not make sense to me and it has become law in a lot of
places.
If you can really keep your pool clean with a 1/4th hp pump, why not
just buy a 1/4th hp pump?
I run my 1HP on a timer that assures one turn over a day and runs
strong enough to vacuum at the same time. I am not sure how a variable
speed pump would save me a dime.

You can probably 95% of the time get by at 25% power (low speed
running)

BUT there might be sometimes when you need full system flow.

In SoCal we have seasonal winds that can super load a pool with dirt,
leaves & other debris.
To clean the pool up quickly, it might take a couple days running
24hrs at full RPM.
At low speed it would take a lot longer. *

But for "typical" / "low dirt load" many hours at low speed could do
the job.

Two speed pumps give you enough flexibility to tailor motor speed to
pool cleaning requirements.

Kinda goes along with the concept of *"side stream" / "kidney loop"
filtering of a hydraulic oil tank as opposed to full flow filtering.

It's all about the total energy used to accomplish the job.

At first glance dual speed pumps might seem silly but they do the job
AND save money.

cheers
Bob

So what's wrong with only running the big pump long enough for a full
turnover (6 hours in my case) and turning it off?- Hide quoted text -

- Show quoted text -


The problem is that you will be using a lot more energy than if you
moved the same amount of water, but did it slower over a longer
time. Instead of moving that water in 6 hours, if you cut the flow
rate down to 1/4 and ran it 4 times longer, ie 24 hours, you'd
reduce energy usage by about 70%, while still moving the
same amount of water. Most of that is from the
fact that the amount of force it takes to move water through
piping is an exponential function of the flow rate.

On Apr 23, 2:23*am, Ashton Crusher wrote:
On Fri, 22 Apr 2011 08:16:36 -0700 (PDT), "





wrote:
In the Polaris pool cleaner thread the subject of variable speed
pool pumps came up. * Which got me thinking about them
again because a friend who has a pool with a single speed
pump is considering options. Doing a bit of research, here's
what I have concluded and I wanted to see if anyone has
addional thoughts.

First, it looks like because of the design of the variable speed
permanent magnet motors, they are inherently more efficient
so you use about 15-20% less energy even at full speed.

Second, the biggest savings in energy come from slowing
the pump down, reducing the flow resistance. *That means
you can run the pump for say 4 times as long, at 1/4 the
flow rate, move the same amount of water, but save 70 to
80% or so in energy.

However, the price of these pumps is very high. *A complete
new pump runs from $900 to $1200 dollars online. *The next
obvious problem is that they typically have only a 1 yr
warranty. * I found an online story where a guy bought
a Pentair Intelliflow one where one of the two small control
boards failed shortly after the warranty ended. *He says
Pentair will not sell the replacement board as a seperate
part or take pumps back for repair. *He would have to buy
a whole new pump. * It looks like Jandy, another major
manufacturer, does sell parts, but the equiv part for their
pump would be $400.

So, this got me to thinking. *It appears to me the biggest
part of the energy savings can be obtained by just going
to a dual speed pump. * And since my friend has a working
pump that is about 5 years old, I'm thinking the most
cost effective solution is to just replace the motor with
a dual speed motor. *We could do that for under $300.

With the variable speed pump, assuming we bought the
lowest cost one, by my calcs, with the energy savings
it would take almost 4 years
to break even. * With the dual speed motor, it would take
less than 2 years. *The pool is seasonal, used 3.5 months
a year. * And it looks to me like the additional savings in
energy going with the true variable speed pump is only
about $50 more a year over the dual speed. *And then
what happens if the fancy electronics on this motor,
which sits outside all year, fails at say year 3, 5 etc?

The only other advantage of the variable is you can fine
tune it to run at exactly the speed you want, but I don't
see a compelling need for that. *Also, there aren't any
utility rebates available here that would alter the
equation. * So, it seems for this app, the variable speed
makes no sense. * If you had a pool running year round,
higher cost electric, rebates, etc, then the results
might be different.

So, swap out the motor for the dual speed for $300? *Any other
thoughts, issues I missed?

I looked at the same issue a few months ago. *I need to have the pump
run at high speed at least part of the time in order for my sweep
system to work. *To do that the least expensive option would be a 2
speed motor installed on my current pump. *But to automate it I also
would need to buy the dual timer control for it which is another $100.

Yeah, that's another issue. In my case, I think it can be done with
a simple switch inside the timer box panel, which has room. That
would allow manual control of the speed. And in this case, pretty
sure that's all that's needed. High speed for draining, backwashing,
fast cleanup, which would be only occasionally. Low for all
circulation. I also saw a pool parts place online that had a motor
end cap with a switch in it to select speed for A O Smith motors.
But it indicated that it had been discontinued. Not sure if anyone
else has a similar device, but it's not the most convenient place
to have a switch anyway.

The sweep/pool cleaner point is a good one. This system has
a seperate booster pump for the Polaris and I would think it
would be enough to work with the pump on low. If not, then
would have to put it to high when using that too, but the Polaris
is manual now as well.



By the time you add it all up it will take several years to break
even. *So I'm still on the fence. *My current pump and motor is 20+
years old and when it goes out I will think about this issue again.- Hide quoted text -

- Show quoted text -

So, swap out the motor for the dual speed for $300? *Any other
thoughts, issues I missed?

T4-


Looks to me like you covered all the issues..... *dual speed is right
choice.
Fancy electronics (unless cheap to replace) will eat up any energy
cost savings when the board fails. *

cheers
Bob

AGREED!
Mark

wrote:
On Fri, 22 Apr 2011 15:13:36 -0700, "Bob F"
wrote:

JimT wrote:
On 4/22/2011 1:05 PM, harry wrote:
On Apr 22, 4:16 pm,
wrote:
In the Polaris pool cleaner thread the subject of variable speed
pool pumps came up. Which got me thinking about them
again because a friend who has a pool with a single speed
pump is considering options. Doing a bit of research, here's
what I have concluded and I wanted to see if anyone has
addional thoughts.

First, it looks like because of the design of the variable speed
permanent magnet motors, they are inherently more efficient
so you use about 15-20% less energy even at full speed.

Second, the biggest savings in energy come from slowing
the pump down, reducing the flow resistance. That means
you can run the pump for say 4 times as long, at 1/4 the
flow rate, move the same amount of water, but save 70 to
80% or so in energy.

However, the price of these pumps is very high. A complete
new pump runs from $900 to $1200 dollars online. The next
obvious problem is that they typically have only a 1 yr
warranty. I found an online story where a guy bought
a Pentair Intelliflow one where one of the two small control
boards failed shortly after the warranty ended. He says
Pentair will not sell the replacement board as a seperate
part or take pumps back for repair. He would have to buy
a whole new pump. It looks like Jandy, another major
manufacturer, does sell parts, but the equiv part for their
pump would be $400.

So, this got me to thinking. It appears to me the biggest
part of the energy savings can be obtained by just going
to a dual speed pump. And since my friend has a working
pump that is about 5 years old, I'm thinking the most
cost effective solution is to just replace the motor with
a dual speed motor. We could do that for under $300.

With the variable speed pump, assuming we bought the
lowest cost one, by my calcs, with the energy savings
it would take almost 4 years
to break even. With the dual speed motor, it would take
less than 2 years. The pool is seasonal, used 3.5 months
a year. And it looks to me like the additional savings in
energy going with the true variable speed pump is only
about $50 more a year over the dual speed. And then
what happens if the fancy electronics on this motor,
which sits outside all year, fails at say year 3, 5 etc?

The only other advantage of the variable is you can fine
tune it to run at exactly the speed you want, but I don't
see a compelling need for that. Also, there aren't any
utility rebates available here that would alter the
equation. So, it seems for this app, the variable speed
makes no sense. If you had a pool running year round,
higher cost electric, rebates, etc, then the results
might be different.

So, swap out the motor for the dual speed for $300? Any other
thoughts, issues I missed?

The water quality in your pool varies with usage. So in times of
low useage, there is ample scope for running the pump slower and
saving electricity.
You will also save heating costs if the pool is heated.
Hit the high speed when the pool is in use and for a couple of
hours afterwards..
If things are OK if the pump is off for a time even better.
A floating pool cover is a good investment too, saves heating,
cleaning, water and chemicals.
A suspended one is less good.



I just don't see the savings. Run the pool less at high speed or run
the pool more at low speed? What's the difference? A more expensive
pump? If it runs more efficient at high speed I can see it otherwise
it sounds like smoke and mirrors.


Low speed produces less back pressure, therefore uses less
power/volume pumped. It is just more efficient. Kind of like driving
55 is more efficient than driving 100.


A lot of that problem gets fixed before you shoot the first drop of
concrete. I spent a little extra money in pipe so the pressures run
lower, even at a higher flow rate than my pump produces. It was
originally designed with one full turnover in ~3 hours with a 1.5HP
pump and I went with a 1HP pump that turns it over in less than 5
hours. There are 5 returns fed with a ring of 3" pipe and the same
size on the suction side. I think the whore thing was about an extra

Smart move, but you still have pressure developed in the filter that would be
lessened by lower flow, thereby increasing efficiency. Maybe, not as much as
normal. My spa, with a cartridge filter, runs 5 psi at low speed, and 20 at high
speed, with the jet bypass open.
$25 in pipe.

On 4/22/2011 11:42 AM, DD_BobK wrote:
On Apr 22, 8:16 am,
wrote:
In the Polaris pool cleaner thread the subject of variable speed
pool pumps came up. Which got me thinking about them
again because a friend who has a pool with a single speed
pump is considering options. Doing a bit of research, here's
what I have concluded and I wanted to see if anyone has
addional thoughts.

First, it looks like because of the design of the variable speed
permanent magnet motors, they are inherently more efficient
so you use about 15-20% less energy even at full speed.

Second, the biggest savings in energy come from slowing
the pump down, reducing the flow resistance. That means
you can run the pump for say 4 times as long, at 1/4 the
flow rate, move the same amount of water, but save 70 to
80% or so in energy.

However, the price of these pumps is very high. A complete
new pump runs from $900 to $1200 dollars online. The next
obvious problem is that they typically have only a 1 yr
warranty. I found an online story where a guy bought
a Pentair Intelliflow one where one of the two small control
boards failed shortly after the warranty ended. He says
Pentair will not sell the replacement board as a seperate
part or take pumps back for repair. He would have to buy
a whole new pump. It looks like Jandy, another major
manufacturer, does sell parts, but the equiv part for their
pump would be $400.

So, this got me to thinking. It appears to me the biggest
part of the energy savings can be obtained by just going
to a dual speed pump. And since my friend has a working
pump that is about 5 years old, I'm thinking the most
cost effective solution is to just replace the motor with
a dual speed motor. We could do that for under $300.

With the variable speed pump, assuming we bought the
lowest cost one, by my calcs, with the energy savings
it would take almost 4 years
to break even. With the dual speed motor, it would take
less than 2 years. The pool is seasonal, used 3.5 months
a year. And it looks to me like the additional savings in
energy going with the true variable speed pump is only
about $50 more a year over the dual speed. And then
what happens if the fancy electronics on this motor,
which sits outside all year, fails at say year 3, 5 etc?

The only other advantage of the variable is you can fine
tune it to run at exactly the speed you want, but I don't
see a compelling need for that. Also, there aren't any
utility rebates available here that would alter the
equation. So, it seems for this app, the variable speed
makes no sense. If you had a pool running year round,
higher cost electric, rebates, etc, then the results
might be different.

So, swap out the motor for the dual speed for $300? Any other
thoughts, issues I missed?

T4-

Looks to me like you covered all the issues..... dual speed is right
choice.
Fancy electronics (unless cheap to replace) will eat up any energy
cost savings when the board fails.

cheers
Bob

heh If I'm reading correctly it looks like the board on the Pentair VS
is about $650.

http://www.poolpartsonline.com/p-815...drive-kit.aspx

Cheap compared to the display panel on my Prius. $3600. Used I got one
for $300.

Jim

On 4/23/2011 2:19 PM, Oren wrote:
On Sat, 23 Apr 2011 12:34:59 -0500, wrote:

Fancy electronics (unless cheap to replace) will eat up any energy
cost savings when the board fails.

cheers
Bob

heh If I'm reading correctly it looks like the board on the Pentair VS
is about $650.

http://www.poolpartsonline.com/p-815...drive-kit.aspx

The board is called a "drive kit"?

That's what it looks like on the blow-up. Part # 28. Price seems about
right to me.

http://www.amazon.com/PENTAIR-INTELL.../dp/B002NJSRME

Jim

On 4/23/2011 3:38 PM, Oren wrote:
On Sat, 23 Apr 2011 15:16:45 -0500, wrote:

On 4/23/2011 2:19 PM, Oren wrote:
On Sat, 23 Apr 2011 12:34:59 -0500, wrote:

Fancy electronics (unless cheap to replace) will eat up any energy
cost savings when the board fails.

cheers
Bob

heh If I'm reading correctly it looks like the board on the Pentair VS
is about $650.

http://www.poolpartsonline.com/p-815...drive-kit.aspx

The board is called a "drive kit"?

That's what it looks like on the blow-up. Part # 28. Price seems about
right to me.

http://www.amazon.com/PENTAIR-INTELL.../dp/B002NJSRME

Jim

Link: "Currently unavailable.
We don't know when or if this item will be back in stock."

I'm ruling out a VS motor for a long timeG



It looks like poolpartsonline.com has one but I understand your concern.

I just replaced my pool pump and built a shed around my pool equipment.
I don't think I'd put that expensive VS pump out exposed out in the weather.

I'll probably look into VS speed when this pump goes out but I'm going
to do my homework first.

Jim

On Apr 23, 7:22*pm, wrote:
On Sat, 23 Apr 2011 13:38:33 -0700, Oren wrote:
On Sat, 23 Apr 2011 15:16:45 -0500, JimT wrote:

On 4/23/2011 2:19 PM, Oren wrote:
On Sat, 23 Apr 2011 12:34:59 -0500, *wrote:

Fancy electronics (unless cheap to replace) will eat up any energy
cost savings when the board fails. *

cheers
Bob

heh *If I'm reading correctly it looks like the board on the Pentair VS
is about $650.

http://www.poolpartsonline.com/p-815...drive-kit.aspx

The board is called a "drive kit"?

That's what it looks like on the blow-up. Part # 28. Price seems about
right to me.

http://www.amazon.com/PENTAIR-INTELL...COVER/dp/B002N....

Jim

Link: "Currently unavailable.
We don't know when or if this item will be back in stock."

I'm ruling out a VS motor for a long time G

If this strategy works, what is wrong with a simple 2 speed pump, or
even 2 pumps.

Nothing wrong with the simple 2 speed pump. That was the point
of my original post. It looks to me like you save the most on energy
usage by going with the variable speed, permanent magnet motor.
That saves about 70%, most of it because of the lower speed, the
rest because the motor is more efficient regardless of speed.

On the other hand, it looks like I can save about 57% by going with
just replacing the existing single speed motor with a dual speed
one. Can do that for $300, vs $900 for the variable speed pump.

The difference between 57% and 70% savings, given the pool is
run 3.5 months here, amounts to about $50. So, it would take
12 years to recover the additional $600 cost of the variable
speed. That plus the possibility of failure of the fancy drive
electronics, etc lead me to conclude the best solution is the
2 speed motor.



I am seriously thinking about going another way. I have been looking
at a DC pump, directly run from solar PV. That may be the best solar
PV idea I have seen. The more the sun shines, the more the pump runs
and that is also when you need it most.- Hide quoted text -

- Show quoted text -

That's an interesting idea. If you rig it together with a 2 speed
pump
so that solar is used just for low speed, might be a cost
effective solution. If it has to be able to run the pump at high
speed,
IMO it will be economically unviable because you'd need a lot
more panels. On the other hand, by my calcs, with the 2 speed
pump running on low, my electric usage will go from $340 a season
down to $150. At $150 a year in usage, I think it would take a
long time to pay back the solar system cost even for the smaller
array running the pump on low, probably rendering
it unviable here in the north with a 3.5 month season.