used hayward DE 7220

[shortdogOH]

Still trying to replace my sand filter.

I have a possible deal on a de 7220 that is somewhat used and brings a load of new questions.

de 7220 seems rather large for my ~20000 gal pool. Is there such thing as too large?

How about the pump? Will my existing 3/4 hp have any performance issues?

I have used some DE in conjunction with my sand filter and found it kind of messy but not too bad. I wonder how much of a pain the maintenance will be. I backwashed my sand filter about twice a week on average. Are DE filters on par with frequency of backwash? I think I looked up that the 7220 uses 9 pounds of de each recharge, 18 pounds a week seems like a lot of extra purchases and hauling if that is the case.

Any other words of advice from DE owners/users?

Thanks

 

[Bama Rambler]

That filter will be fine for your pool. You will need to break it open and clean it about twice a year.

The thing that jumps out at me is the fact that you're backwashing your sand filter so much. I only backwash mine about once to twice a year. You are either backwashing it way too much or you have an incredibly dirty pool.
What is the parameter you're using to decide when to backwash?

I'd think with the DE filter you'd only need to clean it once a year.

 

[shortdogOH]

Thanks Dave. Probably a little of both of the frequency question. My original pressure gauge was broken (stuck on 30) and when I replaced it, the new one did not last only a few weeks before it 'broke' too (stuck on 12). While it "worked" (at least I thought it was working) it seemed 3-4 days for a PSI rise of 10, so I stuck with that schedule,. Waste water always flowed out dark for a good 45-60 seconds when I did backwash, so it seemed like I was doing he right thing.

I am excited about the DE filter, even though it is more pricey, if it can keep my pool cleaner, that will be a major plus. for me.

 

[jblizzle]

That sounds like way too fast of a pressure rise.

We recommend backwashing when the pressure goes up 20-25% of the clean pressure ... sounds like that would be happening every 2 days

Is the water clear?

If you have that much dirt in the pool that is getting filtered out, you will not be happy with the extra work of the DE filter if you have to backwash on a weekly basis.

Something just does not add up ...

 

[shortdogOH]

Jason,

Not sure. I really had trouble getting a handle on the pressure rise due to faulty guages.

The water has been fairly clear at times. I have always had dirt / fine black dust (not sure what it is exactly) in varying quantities. The more I filter and pool vac, the less it is.

Cannot say I have much to compare it to, but I would say my pool gets a little dirtier than normal with the area it is in and the neighbors trees, but not too far from the norm. Chances are that I was just backwashing way too often. Getting a filter with a working gauge and without a leaky multiport would probably go a long way in simplifying my overall maintenance.