Pressure keeps climbing

[Elizabeth]

Hello! I am new here and am hoping that I can get some help. My inground pool was open shortly before Memorial Day and my filter and pump was running just fine. Since that time, the pressure has been pretty stable between 7-9, climbing very slowly to 18 -20. Then I backwash and everything is fine. This has happened twice or maybe three times since opening. This last time however, I decided to clean the filter since it seemed that the pressure was climbing faster than before and I wanted to check the grids and frame (my words, not sure what the real name is) to make sure there are no tears or cracks. Cleaned everything, inspected everything and it looks great. (Only 3 years old). Put everything back together, no leaks, add filter powder, pressure in pool is strong...for two days! Now it’s almost back up to 20. My water is, and has been, crystal clear, but there is something wrong and I can’t figure it out. Now the same thing happened at the end of the season last year and I had it all checked out. No one can figure this out. I’m hoping some of the smart people here can help me out. Thanking you in advance.

[Teapot]

Have you bumped your filter? It takes surprisingly little to clog a filter.

[Elizabeth]

This may fall under the category of stupid questions, but how do I do that. I have a multi-port valve. Would that be necessary after two days of backwashing or a through cleaning?

[ljmesg]

Leave it run. The only indicator I use is my hand over the jets. If any pressure is coming out I am fine.

A clogged filter, filters better than a clean filter.

I eill clean my carto filter then add my granulated chlorine. I am in a warm tropical climate. The granules "clog" the filter and force pressure into the high 20s. My water gets filtered and chlorinated all at once.

Unseen algae and particles will clog your filter as well...force pressure up. This is fine. Thats when you are really really filtering.

When the out jets slow to almost nothing then backwash or clean your carto. A good way to mess up good fiktering is to clean your filter all the time.

Also, any algae you have is due to lack of chlorine and most regular test kids have bad chlorine readings. I was running 1.38 and my kit was telling me I was over 3ppm. No wonder my algae would never go away.

Good luck. If your guage hies to 30psi leavebit as long as you have any out jet pressure. Let it ride and run it longer.

[Teapot]

Whilst I agree that slower filtration is better filtration a dirty filter is a dirty filter. Chlorine will be used up and create more chloramines which you do not want. Also the extra strain on the pump will be costly. Fitting a speed controller and slowing the pump will save a lot of electricity and therefore money and the slower filtration with a clean filter is the correct way to go.

[Teapot]

This may fall under the category of stupid questions, but how do I do that. I have a multi-port valve. Would that be necessary after two days of backwashing or a through cleaning?

It's not a stupid question if you haven't heard of it before. What is the make and model of your filter?

[Elizabeth]

It’s a Hayward Pro-grid D.E. filter DE3620

[Teapot]

Sorry Elizabeth, that model doesn't have a filter bumper. Bumping on some DE filters loosens some of the dirt without having a full backwash and re-coat.
DE filters very fine particles so it gets clogged quicker than sand filters and cartridges. It's the price you pay for using DE so its backwash and re coat by the sound of it, this will lessen as you remove tiny particles you cannot see with the naked eye.
IMO a 2hp pump is a bit powerful for your setup, fine for backwashing quickly but it will be expensive for filtering, You may want to look at a speed controller to reduce the flow down a bit and save probably 50% on your electricity bill and get even better filtration.

[Elizabeth]

Thanks, I made a mistake in my profile that has since been corrected. It’s not a 2 hp motor, it’s a 1 hp motor. One more question...on my filter it says to use 4.5 pounds of filter powder, which I do. Do I add the same amount after each backwash or reduce it to 1/3?

[Teapot]

Hi Elizabeth, 1hp, that's better. In theory, backwashing removes all the DE powder from the grids so you'll add 4.5lbs but watch your pressure gauge, when you started from fresh the pressure after adding the clean DE was? 7lbs? so add DE until it reaches the same pressure.

[Elizabeth]

Thanks for all your help. It’s very much appreciated!

[Teapot]

I hope it works, please pop back and let us know.

[Elizabeth]

After backwashing and getting great pressure out of my jets, it drop to almost non-existent in only two days. Even my backwash water is clean, just a little gray from filter powder. Runs clear in seconds. I’m not understanding why this is happening. There are no leaks. When I last cleaned the filter I did not find any tears or cracks. My pool is clear, no algae. But backwashing every two days just isn’t normal, is it?

[Teapot]

No it isn't, personally I cannot be bothered with the hassle of DE.
DE filters so finely you cannot see the dirt without a microscope 2-3 microns whereas our eyes see to around 40 microns. So it must be clogging with something. Only wish I were there to help, so tricky on the other end of a computer.