Hayward H Series Heater Back Pressure

pickardc

Active member
Apr 4, 2020
27
Oakland, MI
The builder was back out this week. They closed 2 of my 4 returns and still didn't solve the issues and I think will cause problems long term as my only returns are now on the end of the pool opposite the skimmer. Nothing on the sides mid pool. They "think" its a bad pressure switch though I am not certain. I started looking at the curves on the pump and some of the other specs from Hayward and I think they grossly undersized the pump.

The poll is about 22,000 Gals so needs 53GPM to turn over the pool. The Filter PSI is normally 20 which means 46.2 TDH on the return side plus assume there is at least 15 TDH on the suction side (its 185 foot run and 4 ft rise above the pool deck) that would put the TDH at 60 when you look at the curves for the TriStar Max Flo 500 it will never meet the required turn over.



the other issues I have found is the salt cell flow switch is 4 inches from a 90 degree bend. The MFG instructions says there needs to be at least 12 inches of straight pipe before the flow switch. This may be also causing the issue with the salt cell shutting down on anything less than 100% RPM on the pump.
 

JamesW

TFP Expert
Mar 2, 2011
19,364
You only need about 20 to 25 gpm. Your pump is fine.

Forget about "turnover", it's not relevant.

In my opinion, the right answer is to use a flow switch and a flow meter.

What are the model numbers from the pump and the filter?

Is the pump wired for 230 volts?

Has the filter been cleaned?

Did they try to adjust the pressure switch?

Are they verifying the flow rate as they are trying to get the heater to start?
 
Last edited:

JamesW

TFP Expert
Mar 2, 2011
19,364
The pump is fine.

In my opinion, you're wasting time messing with the pressure switch.

I would:

1) Make sure that the filter is clean.
2) Install a flow switch.
3) Install a flow meter.
 

pickardc

Active member
Apr 4, 2020
27
Oakland, MI
the question I have is why would only 2 of the 4 returns have flow at any given time. You have to close off the 2 closest to the pump to get flow from the 2 furthest when the pump is at 100%.
 

JamesW

TFP Expert
Mar 2, 2011
19,364
the question I have is why would only 2 of the 4 returns have flow at any given time. You have to close off the 2 closest to the pump to get flow from the 2 furthest when the pump is at 100%.
Probably a design or configuration problem. If properly designed, installed and configured, the returns should all be roughly equal.

Using an oversized pump is not the answer to a design, installation or configuration problem.

You only need about 25 gpm. If you need a bigger pump than the one you have to get 25 gpm, the system is not right.

In any case, we don't even know what the actual flow rate is.

We need actual measurements of gpm.

Your filter pressure seems to be excessive, which might be due to an undersized filter, a dirty filter or some other problem.

What filter do you have?

Is it clean?

I would make sure that the filter is clean, install a flow switch and a flow meter.
 

pickardc

Active member
Apr 4, 2020
27
Oakland, MI
The filter is a swim clear 150s


I am going to swap the filter out later today. Its been cleaned regularly but 20PSI seems like part of the issue.
 

JamesW

TFP Expert
Mar 2, 2011
19,364
I think that it's a little bit undersized, but it should be ok as long as it's clean.

In my opinion, it's never going to work correctly without a flow switch.

I would just get the flow switch and get it done right.
 

pickardc

Active member
Apr 4, 2020
27
Oakland, MI
I think there is still a flow issue as the Salt Cell keeps getting a no flow alarm. So until the flow coming out of the filter is up adding a flow switch for heater won't make any difference. If I can't get the salt cell on then the heater will have the same issue.
 

JamesW

TFP Expert
Mar 2, 2011
19,364
The Aquarite only needs about 15 gpm to close the flow switch.

If you need to go above 1725 rpm (50%), there's a problem with the system or the flow switch.

Pull the cell and make sure that it's not clogged up.
 

JamesW

TFP Expert
Mar 2, 2011
19,364
Part of the problem is that we don't know the actual flow rate.

I would recommend a flow meter to verify the flow rate. F-30200P flow meter.

I would get the flow switch for the heater because I think that you're going to need it in any case.

Contact Harwil for the correct flow switch that will close at 20 to 25 gpm in 2" plumbing.

Maybe get a vacuum gauge for the suction side and a pressure gauge to install after the filter.
 

JamesW

TFP Expert
Mar 2, 2011
19,364
If you can get a flow meter and a vacuum gauge, that would help us diagnose the problem.

Total head is determined by the vacuum and pressure readings converted into feet of head and added together.

Here is about what you should see with a properly functioning system. (Assumes that the filter pressure gauge is about 8 feet above the surface of the water).

RPM.........GPM.......Total Head....Filter psi
1,725......15 to 30........9 to 11......(-1) to 0
2,400......20 to 40.......19 to 26.......2 to 5
3,000......30 to 60.......25 to 39......4 to 10
3,450......40 to 70.......31 to 49......7 to 13

What is the filter pressure at each of the above RPM settings?

Maybe there's a problem with the suction side or maybe a clogged impeller?

Check actual data against the above reference to see how well the system is performing.

The SWG switch should be closing at 1,725 rpm.

The heater should operate at 2,400 rpm.

What is the exact height of the equipment pad surface relative to the water surface?
 
Last edited:

pickardc

Active member
Apr 4, 2020
27
Oakland, MI
after weeks of trying to trouble shoot and my PB saying 20PSI on the filter was normal I swapped out the filter. After that everything started working properly. The PSI on the filter dropped to 14 as soon as I put a clean filter in.
 

JamesW

TFP Expert
Mar 2, 2011
19,364
The PSI on the filter dropped to 14 as soon as I put a clean filter in.
At what RPM?

What are the readings from the system temperature, heater temperature and Aquarite temperature while the heater is on?

What is the filter pressure at (1,725),(2,400), (3,000) and (3,450) RPM?

The pump should show the power used.

What is the power (watts) for each of the above speeds?

What is the heat rise at (2,400), (3,000), and (3,450)?

Does the heater work at speeds lower than 3,450?
 
Last edited:

JamesW

TFP Expert
Mar 2, 2011
19,364
The problem with running the pump at full speed is that you're using about 2 to 3 times as much power as you need to.

Check the wattage at 2,400 rpm and 3,450 to see the difference.

At full speed, the power usage is probably about 1,500 to 1,700 watts.

At 2,400 rpm, the power usage will be closer to 500 to 570 watts.

See section 6.9. Diagnostic Menu of the manual to see the power usage and other data.

When not heating, you should be able to drop down to about 1,725 rpm, which should be about 285 watts.
 
Last edited: