Pool store says my pump is putting out too much pressure. I have blown 3 grids i am running 18 lb on my gage ( pentair whisperflo 1.5 hp.) ( hayward DE 60 Pro filter) Has anyone had this problem and how to correct it? Should restrict the flow?
Too much pressure blowing DE grids
- Thread starter wbrewski
- Start date
Pool equipment, like filters are designed for 50 psi. So there is no reason they would "blow". In reality, the water flows from outside to inside, so they would get crushed.
Pictures of the damage?
Pictures of the damage?
How old are the grids? They are not made of anything special and wear and tear/chlorine breaks them down.
- Jun 12, 2011
- 3,761
- Pool Size
- 19500
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pureline Crystal Pure 60,000
I have exactly the same filter and until I added a VS pump, my system ran for ten years at a filter pressure of around 30psi. The filter is rated for 50psi.
I have added a photo.
and thanks for the help, I guess the pool store employee does not new his stuff
and thanks for the help, I guess the pool store employee does not new his stuff
Even though the Maximum Working Pressure is listed as 50 psi, it’s not a good idea to run anywhere near that pressure. System components are more likely to leak or fail prematurely.
Also, 50 psi does not tell the whole story. What matters to the integrity of the grids is the pressure differential between the input to the filter and the output of the filter. For example, if a system were 70 feet below a pool, it would add 30 psi to the system, but it would not add any stress to the grids, because the pressure on both sides of the fabric is increased by 30 psi.
In other words, it matters if the pressure is created by the grids or by something after the filter.
At about a sustained 30 psi differential, the grids will begin to collapse and you will get tears at the spot you show because that spot does not have good support.
The Whisperflo is a high head pump and can get up to almost 39 psi. It can definitely damage grids if the pressure is caused by dirty grids.
It would be better to reduce the power of the pump, if possible/practical. If not practical, then keeping the grids very clean would help reduce damage.
Also, 50 psi does not tell the whole story. What matters to the integrity of the grids is the pressure differential between the input to the filter and the output of the filter. For example, if a system were 70 feet below a pool, it would add 30 psi to the system, but it would not add any stress to the grids, because the pressure on both sides of the fabric is increased by 30 psi.
In other words, it matters if the pressure is created by the grids or by something after the filter.
At about a sustained 30 psi differential, the grids will begin to collapse and you will get tears at the spot you show because that spot does not have good support.
The Whisperflo is a high head pump and can get up to almost 39 psi. It can definitely damage grids if the pressure is caused by dirty grids.
It would be better to reduce the power of the pump, if possible/practical. If not practical, then keeping the grids very clean would help reduce damage.
- Jun 12, 2011
- 3,761
- Pool Size
- 19500
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pureline Crystal Pure 60,000
Instead of blowing holes in the cover material, I would have expected it to first crush the internal structure of the grid. But James is right in that pressure differential due to dirty grids, not just high pressure alone is what would cause damage to the grids.
Thanks for all the feedback. I will watch the pressure more closely, and backwash more often.
We recommend backwashing when the pressure rises 20-25% over the clean pressure. And you should do a full tear down and cleaning at least once a year.