Sudden increase in filter pressure

[In-Ground]

Any thoughts on this...

I did a routine back flush on my pool today and when I switched the valve from back wash to filter found that my pool cleaner (zodiac G4 was no longer working). After a quick check found that the flow keeper valve was open and would trip every time after resetting and there was noticeably more suction than usual. I checked the pressure gauge at the filter and psi was at 19.5. i have tried back washing with a rinse several times with no change. Pump is wired for 120 and I confirmed 120 volts at motor connections with a voltmeter. I pulled the flow valve off to inspect internals and sand, both ok. I am guessing it has to be something simple but at this point not sure what to do.

The filter psi usually runs at 8psi and I usually back flush once a week or when the pressure raises to 12-14psi, today was no different with pressure at 12psi before back flush.

Filter (Jacuzzi L250C) and sand were replaced 2 years ago, Pump (Hayward Super Pump 1 1/2HP) was replaced this year.

Suction at skimmer inlet and outlet at the two returns in the pool are more noticeable (both suction and fore from the returns increased.

Seems like something is off with the pump to me, ideas?

 

[JVTrain]

Typically when you see increased pressure in the system (with no changes to pumping hardware) you'll see less flow from returns and into skimmers.

Do you have a dedicated vacuum line or are you running the G4 through the skimmer?

I'm a bit out of my element in diagnosing flow/pressure issues but maybe this bump will get some answers.

Welcome to TFP!

 

[In-Ground]

The G4 is running through the skimmer, no dedicated vacuum line. It's strange, I know what goes in has to come out and any restriction would result in reduced in less return to the pool. That's not the case here, I have more suction and more flow back to the pool than ever. It's like the pump is working overtime and the increased pressure is a result of too much flow for the piping.

Thanks for the bump JVTrain.

 

[tlevy]

Increase flow technically means increased pressure reading in sand filter. When the rpm of the pump is higher, pressure should increase. Is it a variable speed pump? Only other thing that i can think of is a blockage somewhere in the system....


90,000litre, IG vinyl, 1/2 HP Tristar pump, Sandfilter, Aquarite T-15 ASG

 

[In-Ground]

It's not the variable speed pump. Just did a few more checks before I call the pool place. I get 12.5 psi in backwash (used to be nothing) 12.5 psi in rince and 10psi in drain all positions have more than normal suction and return or drain off.

 

[Griswald]

Replace the gauge...

 

[In-Ground]

Gauge was the first thing I replaced, sorry thought I had mentioned that.

 

[Hayward Pool]

Have you pulled the cleaner hose out of the skimmer to see if that makes a difference?

 

[In-Ground]

Yes the cleaner and hose have been out since this started. I had techs from the store where the pump was purchased come and check things out yesterday. I explained everything that was going on and after a few checks they told me that everything was ok and there must have been something in the system that was giving the original low pressure and must have been flushed out during the backwash when the problem started. I'm skeptical on their diagnosis. As for the pool cleaner they say to remove the flow keeper valve from the system.