High Pressure - didn't change when I cleaned cartridges

[alexanderwilliams2415]

Hello everyone,

Today I cleaned my Hayward cartridge filters. Mine takes 8 of them. When I was finished, I ran the pump on high, and the pressure gauge still read 30. How often is this a faulty pressure gauge? Or is there another problem I don't know about? This pool is only 4 years old. Thank you!

 

[Texas Splash]

Are you saying the psi was 30 before and immediately after cleaning? Does the gauge fall to zero when the system is off? How old is the pressure gauge?

 

[alexanderwilliams2415]

Yes that is correct. No, it never falls to zero. Today (the day after cleaning), the lowest it has been was 22 psi. I didn't build the pool, so I'm assuming it is the original gauge from 2019 when it was built.

 

[mas985]

Sounds like a bad gauge.

With that huge filter, there will probably be no difference in filter pressure with or without the cartridges installed. 8 Parallel cartridges will have almost no head loss. I have only 4 cartridges and there is no difference in filter pressure.

 

[alexanderwilliams2415]

Ok thank y'all. Just checking, should the gauge read 0 when the pump is off?

And how do I find what is the normal operating psi? I read the manual and it seems like a lot of factors play into it. But I didn't build it, so how do I know?

 

[Texas Splash]

should the gauge read 0 when the pump is off?

Yes

And how do I find what is the normal operating psi?

Every pool is differently. Basically, record the psi just after you clean the filter. Then watch to see when it increases by about 25%. That's when you know it's time to clean it again.

 

[Texas Splash]

Since you have a VSP, you may need to check the psi reading while on a medium rpm of about 2,300 or so. If the pump is low like 1,400 or below, the gauge needle may not rise at all.

 

[mas985]

Also, because you have such a large filter, you may not actually see a pressure rise in a reasonable amount of time so you may just want to clean the cartridges every year or so.

BTW, what is the pressure at full speed?

 

[alexanderwilliams2415]

Thank you all for your help. Based on what y'all said, it looks like I have a defective pressure gauge. It doesn't go back down to 0 when the pump is off. It's always somewhere between 22-28 psi whether on or off.