The most common mistakes people make when backwashing a DE filter.

There are some common (and not so common) mistakes that people make when trying to backwash their DE filter. If you are having problems with your DE filter, the problem might not be your equipment . . . the problem might be you. (yeah, the truth hurts sometimes).

Here are the most common mistakes people make when backwashing their DE filters

    • Not adding enough DE

Let me ask you a question . . . How much DE can you get into a one pound coffee can?

If you answered “one pound” then please take a moment and kick yourself. A one pound coffee can will hold approximately ONE HALF pound of DE, so if you are adding 5 one pound coffee cans full of DE to your skimmer after backwashing, then you are the reason for the poor performance of your pool filter.

If you do not add enough DE to your filter, then the grids are not totally coated with DE and the dirt that goes into your filter will attach itself right to the fabric on the grids and will not backwash off. This will cause your filter to short cycle (go very short times between backwashing).

    • Only backwashing one cycle

OK, lets see a raise of hands here . . . how many of you only run one backwash cycle (put it in backwash, then put it back into filter) before you add DE back to the filter and go back into the house for another beer?

If you raised your hand, then as you are putting your hand back down, slap yourself in the back of head. Repeat after me “every time I run a backwash cycle, not all the DE and dirt comes out of my filter.”

By reversing the direction of the water through the filter several times, you will do a much better job of flushing out the DE and dirt that is trapped between the grids. You will never get it all out, which is why you need to do a complete filter clean every six months.

    • Running a short “bump” to bring your filter pressure down

I shouldn’t even be telling you this, but here goes . . . if your filter pressure is high and you put it on backwash for, lets say 5-10 seconds, you can get pressure to come down. Like most any shortcut, it is a really bad idea.

It reminds me of a story my mother told me about when she was in college in the 1950’s. They were all making dresses and some of the girls ran short on time so they glued and ironed the seams instead of sewing them. Let’s just say that their shortcuts weren’t the only things that were exposed . . .

But I digress . . . Running a short bump will make a difference for about 5 minutes at the most, then your filter pressure will go back up and if you don’t catch it in time, the high pressure will ruin your grids or manifold.

    • Not adding DE right after backwashing

We have all been there, right? You backwash the filter and look in the shed and all you have is an empty DE bag, or perhaps a bag with only a handful of DE in it, so you leave the filter running for a few days without DE until you can go to Pool Stop to chat with Paul and the guys and get some more DE.

Here is the problem. While you are inside watching the game, all the dirt in your pool is coating your filter grids and it will not backwash off, so don’t be surprised if your filter starts to “short cycle”. So here is the deal: Suck it up, record the game and make that trek to the pool store for some DE, or else turn the filter off until you can go get some DE powder.

    • Not emptying the skimmers or pump trap before backwashing

If you ever clean a DE filter, you might see a bunch of leafy material stuck inside the filter grids, and you shake your head and say “how could that ever get there?”

Here is how it gets there: When your filter pressure increases, your overall flow goes down. When you put the pool into backwash mode, all of the sudden . . . VOILA . . . the flow suddenly increases and a bunch of that stuff that was sitting lazily in the skimmer or pump basket is suddenly flushed out and where does it go? Well, since you are in “backwash” mode, the water enters the inside of the filter grids and all that crap goes with it. So kids, the moral of the story is this: Always empty your baskets before backwashing.

    • Adding DE while the filter is still in “backwash” mode

Before you add DE to your skimmer to recharge the filter, double check to make sure that the pool filter is back in “filter mode, and not in “backwash” mode. This is one of those things that you realize just a little too late, and by the time you realize it, there is nothing you can do about it.

If you add the DE while you are in “backwash” mode, then all that DE will go into the inside of your grids and you are stuck with no good options: Either you can go ahead and put the filter back into “filter” mode and watch all that DE pour back into your nice clean swimming pool . . . OR You can tear apart your DE filter and wash down all the grids manually to get that DE out. IF you are lucky enough to have a multiport backwash valve, then you could put it in “rinse” mode to just blow that DE out to the sanitary sewer, but most people don’t have this type of valve.

If you have made these mistakes before (or just don’t want to make these mistakes in the future), then maybe you should have Pool Stop take care of all your pool repair and maintenance needs. Our cleaners and technicians are trained to do the job right the first time, so you can spend your time enjoying your pool, instead of working on it.

NEED HELP? Having problems with your pool filter? Need a new one but you’re not sure which one to get? Contact Pool Stop today! Give us a call at 972-772-4545 to ask questions or set up an appointment OR hit the “Request Service Quote” button and fill out a service request form so we can schedule your service call. Our team of experienced, licensed professionals is available to help you with expert advice, repairs, and installation.

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