Leaving Pump On With High Pressure

[NullQwerty]

Hey folks,

I made a posting the other day describing how within 1 minute my filter goes above 10 PSI at which time I back wash it (according to manufacture instructions). At the suggestion of one of the the forum members, I'm letting it go longer now and only backwash at about 20-25 PSI (when the return jets barely spray).

So, after adding all the DE, pressure is about 15-17 PSI. I hoped to leave it on overnight, but I'm afraid it's going to rise above 25 PSI over night. My question is, if it does rise above 25 PSI but the pump still runs for another 8 hours after that, am I risking damaging the equipment? Or does it just mean that unfiltered water is reentering the pool and no harm done?

Thanks!

[mkamp1515]

Do you know why the pressure is going up so fast? Maybe you need to clean the grids on the filter. My normal pressure is 17psi. I let mine get to about 22 psi before I backwash (I backwash at least every 2 months anyway, regardless of where my psi is). If you let it run at 10psi or higher than normal for a period of time you do risk damage to the grids which are probably at least $35-$40 each. Hope this helps a little.

Mike

[Poconos]

I think problems arise when the flow almost or totally stops. All you're doing now is heating the water in the pump and eventually something will let go. If you are using sched-40 PVC pipes on or near the pump, PVC softens well below boiling. I suspect there is also additional stress on the pump seal.
Hope this helps.
Al

[cschnurr]

When cleaning out my pump screen basket, the water drains from the lines back into the pool, and I like to run the pump to ensure the pump has kept its prime, and doesn't take to long to draw the water back up. This takes a minute or two.

To prevent draining the water lines, occasionally I'll turn my sand filter to the closed position , clean the basket and then return the filter to normal position. One day last week, out of stupidity, I forgot to return the filter out of the closed position.

During the day the timer ran the pump for 4 hrs.
When I returned the filter pressure gauge was obviously running high (~25psi, typically runs at 15).

When I returned the filter out of the closed position, pressure went back to normal. The only visible damage I could was a small leak (a few drops/minute) at the PVC fitting on the high pressure side of the pump. I replaced it and things look OK.

I recognize I'm extremely lucky, is there anything else I should look out for.

[NullQwerty]

Thanks everyone. I ended up going back out side after 1 hour of letting the pump run.

At that point it was already at 21 PSI so I shut it down for the night. It's good to know though that I shouldn't let it continue to run at high PSI because I probably would have in the future.

Thanks again!

[mshumack]

My DE filter runs about 22psi when it is clean. I backwash around 30psi.
I had a problem when the system was new where the filter grids got covered with plaster paste. I didn't know this was happening. I backflushed quite often (for a week or so) and the pressure would return to normal after each cleaning but quickly get back uo to 25 -30psi within a day or so. Finally I disassembeld the filter and found the plaster paste all over the gids. The backwashing was not cleaning the grids thoroughly. After I washed the grids clean (done without removing grids) with a garden hose the problem never returned. I was just a new pool start up problem.
I don't know if this helps or not.
Good luck