variable vs single speed

Jump to latest Follow Reply
HermanTX said:
With a VS pump, the lower your can run it (low rpm) the less energy is used. So a 2.7 pump will use less energy at a given speed vs the 1.8 hp pump moving the same amount of water.
Click to expand...
This might be technically true, but the difference is small.

For power savings alone, the extra cost of a bigger pump is probably not worthwhile.

The biggest benefit is the difference in noise.

Depending on the speeds, the noise difference can be quite large.
 
  • Like
Reactions: Giri, HermanTX and Bperry
HermanTX said:
The higher HP motor will serve you better in the long run. With a VS pump, the lower your can run it (low rpm) the less energy is used. So a 2.7 pump will use less energy at a given speed vs the 1.8 hp pump moving the same amount of water.

You may want to search the forum on the lights - there are mixed reviews on the longivity of the lights.

A RS AquaLink system is very good, come back here if you have questions on that.
Click to expand...
Thanks. I will stick to RS and 2.7 pump. The difference is around $400. I will make sure and will try to get 2.7 pump. He said for lights, he need to put new wiring and that is why expensive. I will evaluate to decide if needed. May be only one light.. The brand for lights is Jandy and I thought he said 3 year warranty and those are 24watts.
 
  • Like
Reactions: HermanTX
JamesW said:
This might be technically true, but the difference is small.

For power savings alone, the extra cost of a bigger pump is probably not worthwhile.

The biggest benefit is the difference in noise.

Depending on the speeds, the noise difference can be quite large.
Click to expand...
Thanks for all the help. The technician changed the recommendation to only use 1.8 HP as he said 2.7 is not right. Glad we are close to finalize. I got a final quote to install pump and RS control for 4000.

He validated that we already have 3 in pool and 1 in spa that could be changed to color. I did not know until now. I am guessing the app will make it easy to use effectively.

Appreciate help from all of you. It is not easy to find a compatible systems.
 
You will be running the smaller pump at full rpm when using the spa. It is noisy. The larger pump could be run at 2500 rpm and be much quieter.

With the air blower you get away with lower gpm.
 
VS Pump RPM vs Watts Used.PNG

Look at the graph.
What we are trying to show is that if you have a high Hp pump then you would run it at 2200 to 2600 rpm for your spa.
If you have a lower Hp pump then you may need to run it at 2400-3000 rpm to move the same amount of water, ie. through your spa jets. The high rpm on the low HP pump will make it louder and also may use more energy.

At the end of the day, it is your decision based on budget and availability of equipment.

This graph is my VS pump which is shown for example, you would have to plot the same graph for both pumps to get the true difference.
 
  • Like
Reactions: Giri
I talked to the installer and he said my filter can't handle it and not good for it the volume of water from 2.7hp and he is fine to do for couple of hundred more 2.7 but he won't personally do it. Unless all my neighbors move to quiet it may not matter ;-). The backyards are getting tiny as homes are getting a bigger size, particularly in Florida as many of the houses are single floors which makes neighbors too close.
 
Giri said:
I talked to the installer and he said my filter can't handle it and not good for it the volume of water from 2.7hp and he is fine to do for couple of hundred more 2.7 but he won't personally do it. Unless all my neighbors move to quiet it may not matter ;-). The backyards are getting tiny as homes are getting a bigger size, particularly in Florida as many of the houses are single floors which makes neighbors too close.
Click to expand...
He’s missing the point and assuming you’ll be running it at full speed. You won’t ever need to run it at full speed.
 
  • Like
Reactions: proavia, HermanTX, Giri and 1 other person
Giri said:
I talked to the installer and he said my filter can't handle it and not good for it the volume of water from 2.7hp and he is fine to do for couple of hundred more 2.7 but he won't personally do it. Unless all my neighbors move to quiet it may not matter ;-). The backyards are getting tiny as homes are getting a bigger size, particularly in Florida as many of the houses are single floors which makes neighbors too close.
Click to expand...

Sounds like they have a smaller pump in stock that they want to unload.
 
  • Like
Reactions: proavia, dfwnoob, Newdude and 1 other person

Enjoying this content?

Support TFP with a donation.

Give Support
I went to the store and they have 2.7hp as well in stock. He compared performance graphs and he said 1.85 is better for my situation. He said the filter could pop up and pump may get strained for 2.7. I gave up and stick to 1.85. It is not a big deal. He said noise is mostly due to a fan that cools down the motor.

I did not do much research on the quote. But I got one more quote 6k for pump and automation. I feel this is a decent price. It is better than paying $400 for single-speed motor and $800 for a broken display and $500 for wifi antenna. I am getting a brand new upgraded ones and rebate $350. I was about to give up to decide to replace broken motor and the forum helped me. Not sure why he said it does not save any energy to go for variable speed.

It is scheduled for Tuesday. Appreciate everyone's time for helping. Lot of learning for me.
 
  • Sad
Reactions: dfwnoob
Giri said:
Not sure why he said it does not save any energy to go for variable speed.
Click to expand...
They often have no clue about anything that changed since they got stuck in their ways.

They also don't pay your electric bills so they have no incentive to learn what's changed. Check the pics I posted in post #6. Which speed would you rather pay the electric for when the pump runs 8 to 12 hours (?) a day ?

As said before, I even splurge above where I need to run, all the way to 1500 RPMs which pulls a paltry 220W, compared to full throttle.
 
  • Like
  • Love
Reactions: Giri, JamesW and dfwnoob
Giri said:
Not sure why he said it does not save any energy to go for variable speed.
Click to expand...
Just look at the numerous graphs posted in this thread at the beginning and the one posted #47 above. A single speed pumps runs constantly at 3450rpm which uses 2000+kwh. A VS pump can accomplish the same circulation at 2000 rpms and only use 1/4 of the energy.

Giri said:
But I got one more quote 6k for pump and automation.
Click to expand...
Keep us updated once the new pump is in and the automation is set up.
Post the model of the automation if you can. I think you purchased the Jandy AquaLink RS (not sure it is RS-4, 6 or 8).
Ensure the firmware is T.2 on the PCB.
 
  • Like
Reactions: Giri
T.2 is not the latest anymore, W is.

T.2 was superseded by both V and W.
 
  • Like
Reactions: Giri
HermanTX said:
I did look at Jandy website but they do not show the latest revision number. Or I could not find it at least.
Click to expand...

Fluidra, a very transparent and outwardly customer-facing company, no longer publishes that list. I can't even get it from my commercial retailer. Like James did, I just had to extrapolate versions from reading various equipment manuals.
 
  • Like
Reactions: JamesW and HermanTX

Enjoying this content?

Support TFP with a donation.

Give Support
You must log in or register to reply here.
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.
Top Bottom
Back
Jump to latest Follow Reply