How long between DE backwashes?

BPKlein

Well-known member
Jun 4, 2016
90
Lake Dallas, Texas
Hello All,

I am curious to hear from others who run their pump 24 hours a day. We have a SWG and a two speed pump. Running the pump on low rpm, 24 hours a day, we get about 17 days between backwashes. Just wondering in that is close to others normal.

btw... we don’t have an algae problem at all. Nor does the water have any visible debris. What we have is crystal clear water with lots of grandkid activity and sunscreen. 🙂

ThankYou
 

Jimrahbe

Mod Squad
TFP Expert
LifeTime Supporter
Jul 7, 2014
19,132
Bedford, TX
BP,

Wow... I get about 6 months.. I never backwash any more, I just open and clean my DE filters twice a year. I can do this because the pumps run at about 1200 RPM most of the time and my filter pressure is down around a 2 to 5 lbs..

Not saying you should do that at all, but 17 days sounds way too often to me...

What is your clean pressure on low speed???

Are you running at low speed most of the time?

What criteria are you using to backwash when you do?

Thanks,

Jim R.
 

BPKlein

Well-known member
Jun 4, 2016
90
Lake Dallas, Texas
Clean pressure at low speed is 4psi. Clean pressure at high speed is 15psi.

Runs at low speed all of the time.

When the low pressure gets up to about 7psi (equal to high pressure of 20psi) the SWG won’t stay full of water. (It’s clear so it’s easy to tell) So, running on low speed the SWG doesn’t work anymore.

ThankYou
 

Jimrahbe

Mod Squad
TFP Expert
LifeTime Supporter
Jul 7, 2014
19,132
Bedford, TX
BP,

If your filter gets so dirty every 20 days that it reduces your flow enough to shut off the salt cell, then I would be worried about a low level algae bloom, even if you can't see it..

If this were my pool, I would run an Overnight Chlorine Loss Test.. (OCLT)... Overnight Chlorine Loss Test

It can't hurt..

Thanks,

Jim R.
 

BPKlein

Well-known member
Jun 4, 2016
90
Lake Dallas, Texas
OCLT is zero.
CYA 90
FC 8-10
CC 0

The only reason I’m asking is that this is the first summer I’ve tried running the pump 24/7 with the salt cell at 50% as opposed to the 12 on 12 off with the cell at 100% like I have done in years past. On the previous years cycle, a DE cleaning lasted all summer.

ThankYou