I've got an old in-ground pool (+/- 15,000 gallons) with an old Pentair 2000 filter and a Pentair intelliflo pump. Recently, I've been getting block-back of DE from the skimmer when the equipment shuts down. It hasn't in the past. I cleaned the filter when it did it recently, but neglected to add DE. I added a moderate amount of DE today, and there was blow-back again. Any thoughts?
DE blow-back
- Thread starter SCRealtor
- Start date
I'd start by looking for a suction side air leak.
You probably have a big air bubble inside the filter. When the pump is on, it's compressed under 16 or 20 psi -- whatever your system runs at. As soon as the pump shuts off, it expands and pushes water out. The stuff on the clean side gets filtered. The other side pushes DE out through the pump to the skimmer.
It could be as simple as low water level.
You can confirm it by running it a few minutes until everything is humming along and bleed any trapped air out the top of the filter using the air bleed. Then shut the pump off. If no more DE gets shoved out, you know what's happening and just need to find the leak.
See Suction Side Air Leaks - Trouble Free Pool
You probably have a big air bubble inside the filter. When the pump is on, it's compressed under 16 or 20 psi -- whatever your system runs at. As soon as the pump shuts off, it expands and pushes water out. The stuff on the clean side gets filtered. The other side pushes DE out through the pump to the skimmer.
It could be as simple as low water level.
You can confirm it by running it a few minutes until everything is humming along and bleed any trapped air out the top of the filter using the air bleed. Then shut the pump off. If no more DE gets shoved out, you know what's happening and just need to find the leak.
See Suction Side Air Leaks - Trouble Free Pool