High backpressure when valve is at recurculate position

Cassou129 · Postby **Cassou129** » Sun 03 Jul, 2011 22:31

Hi
I have an ingroundpool (14x28x5) with a 250sand filter and 1.5hp pump. Pipes are1.5 in
The backpressure when the valve is at recurcukate is at 23psi and when it is at filter goes up to 25 psi
I just change the sand in my filter 2 weeks ago, hoping that the pressure would go down
Water flows at high flow in all the return and I also removed the eyeball. The pressure remains high even at recurculate. I'm also bypassing my heather so the restrictions does not come from there.
Would anyone have suggestion :idea:

Thanks

TSH tech · Postby **TSH tech** » Mon 04 Jul, 2011 02:14

When you say you have a 250 sand filter, are you referring to a Jacuzzi Laser 250 sand filter? Or it's 250lbs.?
Has the pressure always been high since day 1?
When you say heater, you mean gas heater, NOT solar panels, correct?

Here's my preliminary assessment assuming the above is true; you have a 1 and a half horsepower pump with 1 and a half inch pipe. That size pump is slated for 2 inch pipe. That's a pretty powerful pump, strong enough to push water up a solar system. 25 psi doesn't seem all that unreasonable given the information you have provided. This powerful pump is trying to ram water through the filter with an output pipe of 1 and a half inches, yes, there's going to be some unusual high back pressure going on there. The best possible solution, and most affordable, if you are concerned about the extra pressure, is the have the pump impeller changed out from a 1.5 hp rated one, to a 3/4 rated impeller. Three quarter hp impeller is ideal for pipe size of 1.5 inches.

Cassou129 · Postby **Cassou129** » Mon 04 Jul, 2011 03:41

[quote="TSH tech"]When you say you have a 250 sand filter, are you referring to a Jacuzzi Laser 250 sand filter? Or it's 250lbs.?
Has the pressure always been high since day 1?
When you say heater, you mean gas heater, NOT solar panels, correct?

The assumptions are right my sand filter is aJacuzzi Laser 250 and the heater is electric
The pressure with my older pump at install was around 20. It just got higher with time.
But since I chage filter the pressure was always high.
So I either need new pump or down grade this one.

Thanks for the input

Fltech · Postby **Fltech** » Thu 28 Jul, 2011 21:58

Before you start changing the pump around there is one thing that is off. You said the filter PSI gauge was showing 23# when in recirculate. This possibility shows a problem with the PSI gauge. What is the pressure when the pump is off?