When to Replace vs. Clean DE Filter?

[Watermom]

Bumping this up to see if someone can reply for you.

[Poconos]

Losing prime is due to an air leak somewhere. Be aware that a leak that seems insignificant for water, such as a drop every couple minutes, can be significant for air. Over the 12 hours the pump is off even the slightest leak will probably cause the water to drain out of the pump basket and lose prime. As for the DE problems, I'm pulling a Sargeant Shultz...I Know Nothing.
Al

[Hszwill]

Al, you were right, and here is how I found out where the leak was.

The first thing I did was swap clear dome lids between the main pump and the twin that runs the deck jets. The pump continued to lose its prime within hours of being turned off, so I knew that there must be an air leak somewhere else. Next, I let the hose gently run over the equipment in various places, but I never saw any noticeable bubbling to lead me anywhere. Upon leaning in closely, like some kind of ease-dropping detective, a faint high-pitch sound was heard at the Jandy valve that controls water flow from the skimmers and main drain. We took the valve top off, inspected the o-ring, and discovered that it was cracked! Since the set-up is twin to the deck jets line, we moved the o-ring from that one over to the main pump, and it hasn't primed this nicely since the first year we opened the pool! I so appreciate the care and help on this forum. Thank you for teaching me along the years.

Shannon

[albertgarrido]

Sounds like you found your problem.
However, just in case, I've also found another thing that causes air leaks.

This has happend to me and took a while for me to figure it out.

Not sure what kind of valve's they are (I think Jandy), but the valves that allow me to control my skimmers and main drain have been the culprit in the past. These valves are the type you have to loosen a little before you can open/close them. Well sometimes, if they ae too loose they allow air into the system. Funny thing is they do NOT leak. So when my filter looses suction after being off for a while and won't prime on it's own, that is usally the first thing I check, and 9 times out of 10 it is exactly that. The other 1 time was that the O-ring on my pump was worn.

I'm thinking this should be a "sticky" as one of the first things to check when a filter won't prime. What do you think?