high pump pressure

[neilg]

When we built the pool 10 years ago, the pressure at the filter was typically 20 -30 psi. I have a cartridge filter that I replace yearly and clean about once a month. The pressure now is about 35 psi and my filter is about a year old and not too dirty, but probably could be replaced. I took the filter out completely and ran it for about 1/2 hour with no filter at all and the pressure was 28 psi. I would expect this pressure to be about 20 psi like it used to be with a brand new filter.

The return to the pool flows first through our heater. Then it can divide between our spa jets and/or the in floor cleaning system. Before it gets to the in floor cleaning system, it can redirect to a water spout we have in the shallow end.

To make sure I don't have any blockage, I bypassed the heater. Then I directed it all to the spa or all to the in floor cleaning system. When it went to the in floor cleaning, I redirected it all to the water spout or all to the in floor cleaning system. Doing all of this there was no change of pressure at all. This makes me think there is no blockage in the returns as I have sent the return water along a number of different paths with no change in pressure.

The pressure gauge reads 0 at rest. I also replaced that about year ago when I replaced the filter hood and have not had any problems with the new gauge. The old gauge read the same pressure as the new one before I replaced it. I also replaced the pump about 2 years ago with the exact same pump as was built into the pool.

If I was to replace the filter again, I would probably have a pressure of about 28 psi. I'm not sure what could be causing my pressure to be nearly 10 psi higher than when we built the pool with a fresh filter.

Any ideas on what might be causing the pressure increase?

Whoops, just noticed the info on my pool at the bottom is wrong. I will update that:
19,000 gallons
in ground
Cartridge filter - Unicel C-9419 200 sqft
Centurion 2hp pump
Orlando, FL

thank you

 

[mas985]

I have a cartridge filter that I replace yearly

Why so often? I just replaced my cartridges after 10 years of service. You really shouldn't need to replace cartridges that often. It could be an symptom of another issue.

There should be a second pressure gauge on the in-floor cleaner valve. How does that pressure compare to what you had before. Or when you say in-floor cleaner do you really mean a suction cleaner?

 

[neilg]

I've always had the pressure go up over time and replacing the filter seemed to resolve that until it went up again. I didn't think the filters lasted 10 years though.
Yes, it's an in floor cleaner. We have pop up jets around the pool bottom that push the debris towards the drain. The valve that operates the cleaner does not have a pressure gauge for it. It does have a place to put a pressure gauge, but that is sealed from when they put the pool in.

However, I have diverted the water away from the in floor cleaner to the water spout that we have and in doing so, the pressure did not change, so it makes me think there is nothing wrong with either of those.

19,000 gallons
in ground
Cartridge filter - Unicel C-9419 200 sqft
Centurion 2hp pump
Orlando, FL

 

[mas985]

The only reason to replace a cartridge is if the media is ripped or there is damage to one of the end caps and so it is allowing debris pass the cartridge. It is likely that previously, you just did not clean the cartridges properly. Here is a good thread on how to clean cartridge filters: Re: How to clean a cartridge filter. Did you ever try soaking the cartridges in TSP and/or acid before replacing?


As for the change in pressure, perhaps you could post a picture of the pad equipment. Also, has anything in the plumbing changed since you noticed the change in pressure? Double check all valve settings to make sure you are not restricting flow anywhere.

 

[neilg]

The plumbing is all original. I do have a new main pump that is 1 1/2 hp (same rating as original). The new pump is about 2 years old.

Here are some pictures of the setup. As I was saying, I can divert the water a number of different ways and I have tried bypassing the heater, bypassing the in ground cleaner, bypassing the spa, directing all to spa. All the changes to water direction have no affect on filter pressure.

 

[duraleigh]

All the changes to water direction have no affect on filter pressure.

Then you likely need a new gauge. Each change you make in flow either lowers or increases the resistance in the system. That resistance should be demonstrated with changes in the psi.

 

[neilg]

The gauge does read 0 at rest and it does seem like my return flow is diminished. Is there a way to test the gauge?

 

[duraleigh]

The gauge does read 0 at rest and it does seem like my return flow is diminished. Is there a way to test the gauge?

Other than replacing it (pretty cheap), I don't know how it can be tested.

That said, can you choke down the outlet (pressure side) of the pump anywhere? In other words restrict the flow a lot (it won't hurt the pump) and your psi should rise dramatically.

 

[mas985]

Have you tried tapping the guage while the pump is running?