Bypass HP In The Off-Season?

revitup

Gold Supporter
Bronze Supporter
Nov 30, 2019
419
Pawleys Island, SC
Pool Size
8500
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite (T-15)
I turn our HP to 'standby' in the off season (there is no 'off' setting on the Hayward HP) and allow water to circulate through it when the pump runs (4 hours/day). There is a valve and the capability to bypass the HP. Is there some reason I should? Sorry if this has been asked before.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
24,068
Northern NJ
Pool Size
35000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
Really does not matter with a SS pump.

If you had a VS pump taking your HP out of the loop would let you run the pump at a lower RPM.
 

revitup

Gold Supporter
Bronze Supporter
Nov 30, 2019
419
Pawleys Island, SC
Pool Size
8500
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite (T-15)
Really does not matter with a SS pump.

If you had a VS pump taking your HP out of the loop would let you run the pump at a lower RPM.
I'm not following that. Why would I need to run a VS pump at higher RPM with the on 'standby' HP in the loop?
 

PoolGate

Gold Supporter
TFP Guide
Jun 7, 2017
5,448
Damascus, MD
Pool Size
29000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Jandy Aquapure 1400
Heater bypassing has come up a lot lately. I'm not sure it makes a difference whether the water is moving or not. It matters for the water getting stagnant but does it matter for heater life? And if you empty out the heater lines totally is that a good thing? Properly balanced water has been shown to do the most good for all equipment. Not sure if anything else matters.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
24,068
Northern NJ
Pool Size
35000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
I'm not following that. Why would I need to run a VS pump at higher RPM with the on 'standby' HP in the loop?

I said:

If you had a VS pump taking your HP out of the loop would let you run the pump at a lower RPM.

Taking the HP out of the water loop with your heater bypass lets you run a VS pump at a LOWER RPM. Not higher RPM.

A HP has smaller heat exchanger piping then a gas heater and requires a higher RPM to achieve the same flow with a VS pump. If your SWG can run with a minmimum flow at 1,200 RPM it may take 1,900 RPM for the same flow when a HP is added. So if not using the HP and bypassing it you can reduce your VS RPM and get the same flow for the SWG flow switch.
 

revitup

Gold Supporter
Bronze Supporter
Nov 30, 2019
419
Pawleys Island, SC
Pool Size
8500
Surface
Fiberglass
Chlorine
Salt Water Generator
SWG Type
Hayward Aqua Rite (T-15)
I believe we're saying the same thing.

You said:
If you had a VS pump taking your HP out of the loop would let you run the pump at a lower RPM.

I asked:
Why would I need to run a VS pump at higher RPM with the on 'standby' HP in the loop?

You answered:
Taking the HP out of the water loop with your heater bypass lets you run a VS pump at a LOWER RPM. Not higher RPM.

If I can run a VS pump at a lower RPM with the HP out of the loop then I would have to run the pump at a higher RPM with the HP in the loop.

I do understand the smaller piping requiring a higher RPM for the same flow. and that would be important in satisfying the SWG flow switch. I guess I should have mentioned that the SWG is not functional anyway in the off-season with the water temp at 49 degrees. What i deduce from this is that the HP being in or out of the loop is only important if I'm concerned with flow rate as it pertains to turnover.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
24,068
Northern NJ
Pool Size
35000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
Do you have a SS pump or VS pump?
 
Thread Status
Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.