DE backflushing trouble

sandman300z

Member
Sep 14, 2013
7
Ok, Im stumped. I have a DE filter and when I backflush I watch the water coming out and wait for it to clear up. Now when Im backflushing the water coming out is clear from the start and never shows dirt. It appears that it not flushing the filters. Any ideas? Thanks in advance.
 

pwrstrk

TFP Expert
LifeTime Supporter
Aug 17, 2012
4,758
Elverson Pa.
Welcome to TFP !!

What brand of filter is it ? How much has the pressure risen when you backwash from the clean pressure ?

After you backwash you are recharging with DE correct ? I ask because I've seen people forget to recharge after a backwash.

Please put all your pool info in your sig. It will help us better help you !
 

sandman300z

Member
Sep 14, 2013
7
Sorry, guess that would help. Its a Purex DE Model SMBW 4036 with a centurion 1 hp pump. They pool is apprx. 15000 gl. I have only been in the house for three years and I know the pool was put in in the late 70's. Wouldnt be surpirsed it this is the original sysytem.
 

jblizzle

Mod Squad
TFP Expert
LifeTime Supporter
May 19, 2010
43,238
Tucson, AZ
If you do not see at least white DE coming out, then something is amiss.
Are you adding DE or fiber media after each backwash?
Do you have a multiport or just a plunger backwash valve?
 

sandman300z

Member
Sep 14, 2013
7
I am adding DE after each backwash and not even that is coming out. The water just looks as clean as could be. The pressure drops to normal when I do backflush but rises shortly after.
 

sandman300z

Member
Sep 14, 2013
7
I open it up about twice a year at least and deep clean the filters. Last time was about a month ago. As for valve not sure, Im new to the pool scene. If your talking about on the filter its self Im not sure what its called. There is a lever I mover on the bottom to backflush and then back to send it to the pool.
 

jblizzle

Mod Squad
TFP Expert
LifeTime Supporter
May 19, 2010
43,238
Tucson, AZ
Hmmm ... does not sound like you could have been on the wrong valve setting. After you backwash, have you opened it to see if all the DE is still there? You are adding the DE while on filter mode right?
 

sandman300z

Member
Sep 14, 2013
7
When I opened it up yesterday the filters where still dirty. I didnt add any DE then because it didnt flush the old out. Everything seems to be working just fine, lots of water coming out when I backflush its just not cleaning the filters when I do. Sure got me stumped.
 

sandman300z

Member
Sep 14, 2013
7
I guess I should add that I live in AZ and have lots of dust. When I do back flush the water is dirty and I would let it run til it cleared up. Sometimes I would repeat the process a couple of times. I would then add new DE when I put it back to filter.