Multiport valves on DE filters

TishTash

Bronze Supporter
Aug 8, 2018
155
Merrick, NY
Quick question: I know multiport valves are nearly a necessity for sand filters, but do DE filters benefit much from them?

I can see how vital it’d be to run the system both backward (Backwash) and forward (Rinse) in a sand filter (where one has to unsettle and then resettle the sand), but I can’t seem to justify anything that advantageous with a DE filter that isn’t accomplished by just letting it drain out passively (especially in my case, where the filter is below the water line).

In fact, in a DE filter, the most that true multiport backwashing (where the water runs from the return TO the filter inlet to waste) would accomplish is maybe dislodge some more DE from the fingers, but that seems to be something that bumping — followed by draining with the return valve open (vs the skimmer valve) — probably does just as well.

Conversely, it seems to me that multiport rinsing (water running from filter inlet to return to waste) doesn’t accomplish squat, save recoating the filter some with the remaining DE, while basically sending filtered water to waste; one could just run the filter normally and not even waste any water.

Videos of multiport valves on DE filters specifically seem to agree that after backwashing and rinsing, you still need to manually drain the filter to get the larger chunks of used DE out anyway.

Anyway, I was just curious as to everyone’s thoughts. Thanks in advance.
 

HermanTX

Gold Supporter
May 20, 2020
690
Katy TX
My view is that a Multiport valve is just as important for a DE filter as it is for a sand filter.
Also it gives the capability to recirculate without going through the filter.
I agree that a thorough cleaning of a DE filter you will see large chunks of DE still in place however if you commit to a routine backwash you can remove sufficient debris and DE so when you recoat it is with new DE.
 

TishTash

Bronze Supporter
Aug 8, 2018
155
Merrick, NY
My view is that a Multiport valve is just as important for a DE filter as it is for a sand filter.
Also it gives the capability to recirculate without going through the filter.
I agree that a thorough cleaning of a DE filter you will see large chunks of DE still in place however if you commit to a routine backwash you can remove sufficient debris and DE so when you recoat it is with new DE.
My only contention is: Just how often does one honestly use recirculate?
 

Jimrahbe

Mod Squad
TFP Expert
LifeTime Supporter
Jul 7, 2014
19,189
Bedford, TX
TT,

I just got through removing my MPV on a rent house pool.. I have not used it in years... That DE filter is configured just like my cartridge filter at my house.. I did add a 2 way Jandy valve between the pump and the filter input, so I can removed the pump lid without dumping the water in the filter.

I gave up backwashing a long time ago.. I just open and clean all my filters twice a year.. I can do this because I have VS pumps running at about 1200 RPM most of the time, so there is almost no filter pressure.

Thanks,

Jim R.
 
  • Wow
Reactions: TishTash

TishTash

Bronze Supporter
Aug 8, 2018
155
Merrick, NY
I was told that my filter (Hayward EC65A) can’t & really shouldn’t be used with a multiport. I dispute that, but I can see why one shouldn’t stress about not having one, as I mentioned above.