I just replaced my Hayward ProGrid 36 with the exact same filter. Starting pressure with No DE is 12 PSI. After about two hours the pressure goes to 20-30 PSI. Pool is clear so the filtration debris isn't causing the pressure rise. I run the backwash and it comes out clear. After running the backwash for just a few seconds the pressure will return to the starting pressure. I'm running no DE in it to rule out filtration debris for the pressure rise. Any idea what could be causing this rise in PSI over such a short time?
High pressure Hayward DE filter
- Thread starter Zwillard
- Start date
Welcome to the forum. 
I am not a DE filter guy, but I think they are not intended to be operated without DE.....someone else will chime in.
I can tell you without doubt that your filter is catching something.....you just can't see it.
I would stop that operation until someone posts about running without DE. Meantime, we will all want to see a complete set of test results.
I am not a DE filter guy, but I think they are not intended to be operated without DE.....someone else will chime in.
I can tell you without doubt that your filter is catching something.....you just can't see it.
I would stop that operation until someone posts about running without DE. Meantime, we will all want to see a complete set of test results.
Don’t operate without DE. You should take the filter apart and clean the grids. Then add DE at startup.
Check for organics by doing an Overnight Chlorine Loss Test.
Can you post all chemistry readings?
Check for organics by doing an Overnight Chlorine Loss Test.
Can you post all chemistry readings?
