Pool will only drain to a certain point

[dcaton]

Trying to do a partial water change. I am only able to drain the water so far via the main drain (maybe a foot below the skimmer opening), before the pump starts sucking air. The skimmer is off, of course. No amount of priming will get the pump to work again, until I refill the pool.

I'm thinking that downward pressure exerted by gravity on the water assists the pump, and when the water level gets to a certain point the pump doesn't have enough suction power on its own to draw any more water from the pool. Does that make any sense?

At my previous house with a similar sized pool and pump, I was able to drain the pool much further although I never tried to drain it completely (nor am I trying to do so now). However at my previous house, the pump was much closer to the pool, so I imagine that's a factor.

Yeah, I should probably just go get a submersible pump, but I haven't had a need for one before and I'm not trying to empty the pool, just do a partial water change.

 

[ajw22]

Many pools main drain do not work well and draw water on its own.

I think every pool owner should have a submersible pump.

 

[Newdude]

This $83 pump is a beast if you use a 1.5 inch hose. It also has the 3/4 attachment for a standard garden hose.

My 1/3 hp pump lasted a decade but took forever. So far the new pump is going strong but even if it doesn't last, I'd rather replace it every few years than wait for the smaller pump.

 

[dcaton]

This $83 pump is a beast if you use a 1.5 inch hose

Thanks. Great minds think alike . I ordered that same pump last night after seeing another recommendation here (perhaps from you?). Guess it can never hurt to have one on hand although I've only had a need to drain a lot of water one other time in about 6 years of owning homes with pools. But it's not expensive.

 

[Newdude]

A submersible for pool owners is like a wet / dry or shop vac. It's rarely needed but it's worth it's weight in gold when it is.