Pre-mix DE Filter Media?

Hi All,

I installed a new Hayward Pro-Grid Vertical DE4820 this year and after backwashing and adding DE filter media (6 lbs. each time) four times, it burned out my 3 year old Hayward 1 HP pump. I took the pump apart and the technician at Leslie's told me that the DE powder gummed up the motor and burned it. Leslie's technicians are convinced that I should pre-mix the DE in a bucket of water and then pour it into the skimmer. Anthony Sylvan and others tell me that DE does not require pre-mixing. The instructions clearly state to add DE slowly into the skimmer closest to the filter until it's absorbed by the plumbing.

I purchased a new pump and plan to pre-mix the DE in water before pouring the next time. I was also thinking of using Aqua Perl, the DE Alternative, and use 3 lbs. instead of 6. Any comments or suggestions will be greatly appreciated.

Thanks in advance. Johnny

Johnny,
Welcome to the forum. 6# of DE is a lot of DE and I can understand that it would probably clump if not premixed. I routinely add about a cup to my sand filter and I premix even that little amount because I believe it provides a more even coat on top of the sand. Whether it could cook a motor is debatable as I think you should see other signs of a problem like reduced or blocked water flow, excess noise, or something, before it cooks.
Al

Johnny,

Welcome to the Forum.

I can understand the motor burning out if you added 6lbs of DE after backwashing each time. You need to check the procedure for backwashing The DE 4820. If you don't have it, this is what I do when I backwash my DE 3600.

Stop the puimp. Set the multiway valve to the filter in the backwash positin.
Open the main drain as well if you have one. You need to maximise flow when backwashing.

Start the pump, and look at the glass on the waste connection. It will turn dirty/white. When it is clear shut the pump off.

Switch the multiway valve back to filter, and start the pump. Filter for about 3 - 4 minutes. Then stop the pump.

Switch the multiway valve to backwash, and start the pump. Check for more DE in the sightglass, and when clear shut the pump down.

Continue these steps until the sightglass is clear. Shut the pump down and switch to rinse on the multiway valve. Start the pump and rinse for about 3 minutes. Then stop the pump.

Switch back to filter, start the pump, check the pressure on the filter, and at this point you can add the DE slowly through a skimmer, 1lb. at a time. There is no need to premix, but you have the option.

I would continue to use DE instead of Aqua Perl.

Hope this helps.

Pat

My Hayward DE filter uses 7.5 pounds and I simply mix it in a 5 gallon pail with about 3 gallons of water to form a slurry and then slowly pour that into the skimmer with no problems after 8 years of doing this.

Thanks to all who responded and have a great 4th!

Johnny

Jc, welcome aboard, you've made a great choice caring for your pool yourself (rather than having your pocket picked by some pool dudes who may or may not know what they're diong) and comming here to learn how to do it :)
I find it very ! hard to believe that a clot of DE could burn out your pump, did they also throw it into a barrel of water and convince you that it wasn't a witch when it sank? Something else was going on that they didn't realize.
However, you're not backwashing properly and neither are the folks who told you how to do it. I've posted this info a number of times here, here's what I could find easily:
http://www.poolforum.com/pf2/showthread.php?p=13564
http://www.poolforum.com/pf2/showthread.php?t=2562
http://www.poolforum.com/pf2/showthread.php?p=15802
There are 2 points here, insert the rinse cycle after every backwash and only add 80% of the recomended DE when recharging the filter! In your case the amount of De to add is just under 5 lbs.
I work on hundreds of these units per year (however that's just a fraction of the number of pool owners that Leslies misinforms a week ;) ).
Good luck with the pool and have a great 4th! - Waste