PSI loss in zones, 13 in one zone but 17 in another

[Mr loop]

New here, so i hope i post this in the right place.
I am losing psi as the system changes zones. Starting in the deep end at 17 and ending at the shallow end with 13. I have just replace the gear parts and rubber rings but its still not working right. So the shallow end stays at 13 and never changes . I am a new pool owner for about 5 yrs, so if i missed something just let me know.

Equipment :
20k IG plaster chlorined (using Calcium Hypochlorite) pool
Pump : Pentair IntelliFlo, running at 2500 rps for 10hrs
Filter : Hayward SwimClear C3030 325 Sqft. I just got it a few weeks ago.
and the 5 port Caretaker 99 system for the pop-up heads, i think its Polaris

all parts are 2-3 years old and everything seems to be working, just not this psi thing.
Also i should point out that the psi in all zones were working correctly before the new filter. I had a sand filter i did not like.

 

[JasonLion]

Welcome to TFP!

Most likely the in-floor cleaning heads (or possibly the piping, but that is less likely) in the zone with higher pressure are partially blocked.

 

[Mr loop]

How would being partially blocked lower the psi? You would think that it would raise it.

 

[mas985]

So what was the pressure with the old filter? You said everything is working ok but does that include the zone at 17 PSI?

Sometimes when changing filters, debris can get into the return lines which can be problematic for in-floor heads. Can you remove the heads with the high pressure and clean them out?

 

[Melt In The Sun]

i think your system works fine. Different lengths of pipe run on different zones is normal, and so your pressure will change as it rotates through the zones. You probably just never noticed before!

 

[malcolmb5325]

normal operation for the 5 port water valve is between 15 - 19 psi, depending on how many heads per line. If the change has just happened then i would check to make sure all the heads have their nozzles in place. Have you taken the heads out lately? if so did you replace them back in the exact same position? VERY IMPORTANT.

 

[Melt In The Sun]

if so did you replace them back in the exact same position? VERY IMPORTANT.

This is completely impossible to maintain and makes no practical difference. Anytime anyone steps on a head, or it doesn't quite pop up all the way because there's a piece of sand in it, they get out of sync. It is not important.

 

[Mr loop]

I have replaced 2 heads, but that was after the new filter so its still the same.
Pressure with the old filter was right at 12 psi running the motor at 2600 rpm. I am running it at 2500 now, but all the heads now have standard nozzle insert. They were added after the new filter, so i know that's not it
I am thinking i might have something off in the new pluming, but i got it a Lessie's so they aren't going to do anything more about it i, asked already.
I am also thinking that it could just be old heads and they might be leaking, and by this i mean that if one has a small crack in it air can get in the line and now 2 or even 3 zones can be out of whack. I got the house about 5 years ago and i know it was drained when i got it. The heads seem to be about 20 years old, installed in the 90's or 80's maybe.

Thanks for all the help and please fill free to ask more questions.

 

[mas985]

but all the heads now have standard nozzle insert.

So what did they have before?

ANY change to the plumbing will change the pressure so it would not be unusual for the pressure to increase if your are restricting the flow more than you did before. You have a lot of changes going on which makes it very difficult to know for sure if it was something that changed or another type of issue.

Does the zone that is higher in pressure have the same amount of heads as the other zones?

Are the heads in the high pressure zone exactly the same as the other zones?

If all the zones have the same heads and the same number of heads, the pressure of each zone should be about the same.

 

[malcolmb5325]

Melt in the Sun, you misunderstood me, what i meant was the heads have to go back into its original position as per the original infloor design, otherwise the hydraulic design of the system will change and also the cleaning radius will not work. The rotation positions will of course go out of sync over time and can be easily rotated to put them back in to sync as part of a pool maintenance routine.

 

[Melt In The Sun]

OK, yep I see what you mean. If you put the wrong size orifice in, it won't work right. We've had some folks recently saying that the directions have to be in sync...blah blah blah.