New Pump and hardly any flow?

[JeanZ1]

Hi there, I just had my Jandy single speed (1.5hp) pump replaced with a Jandy variable speed (1.85hp) pump. The issue is a full power (3450rpm) I have like 1/4 of the flow out the returns as I used to. What could be wrong?

 

[proavia]

What is your filter pressure?
When is the last time the filter was disassembled and thoroughly cleaned then recharged with DE?

Your PoolMath logs from 3 days ago don't look bad. CYA is a bit high at 100.

If filter has a multiport valve, (with pump off) set the MPV to recirculate and let us know if anything changes flow wise.

 

[JeanZ1]

Sadly no multiport. The pool was just opened last week and flow was good just a couple hours prior to the pump replacement. I will give backwashing the filter tomorrow a go.

Yeah, got a little overzealous with the CYA. I somehow think I got a false read of 20, appears it was closer to 50. Guess I'll chalk it up to first read of the season.

 

[Lake Placid]

The pool was just opened last week and flow was good just a couple hours prior to the pump replacement.

What’s the water clarity? A lot of organics when you opened? Good chance the filter is plugged with debris from the winter mess.

 

[proavia]

Break the filter down to do the cleaning.
Remove the grid and grid assembly (any loose parts), put the filter top and clamp back on (without the grids), tighten the clamp properly, start the pump and see if the water at the returns is back to your normal. If it is, the filter was plugging up. If not, there is another issue we can discuss after that test.

If the filter is plugging up quickly, you may have a nascent algae bloom - do an Overnight Chlorine Loss Test to confirm whether you have algae or not. If algae, you will need to do the SLAM Process.

 

[JeanZ1]

Well, I braved the rainy night an backwashed (I know me, it would have kept me awake). No significant change. I did notice after I finished and added more DE, it was spitting it into the pool.

Ugh, I've never opened the filter and it kind of intimidates me, but I will give it a go.

 

[JeanZ1]

Break the filter down to do the cleaning.
Remove the grid and grid assembly (any loose parts), put the filter top and clamp back on (without the grids), tighten the clamp properly, start the pump and see if the water at the returns is back to your normal. If it is, the filter was plugging up. If not, there is another issue we can discuss after that test.

If the filter is plugging up quickly, you may have a nascent algae bloom - do an Overnight Chlorine Loss Test to confirm whether you have algae or not. If algae, you will need to do the SLAM Process.

Problem solved! As I prepared to dig into taking the filter apart, I decided to check all the valve settings according to my photo of normal operation. One was set differently, put it back to where it should be and voila, all good. I didn't check before because I didn't think replacing the pump would have anything to do with the return side of the pump. Why would they move a valve?
Thanks for your help, much appreciated.

 

[Lake Placid]

If it was a valve on the return side, and your pad level is below water level, they may have closed the valve to prevent backflow of water during the pump replacement. Then they just didn’t fully open it. Just a guess as I’m unfamiliar with your setup.