I have a whisperflo pump that loses prime after the pump is turned off. When the pump is running there are a few air bubbles visible in the lid. There are no visible leaks during operation of the pump. As soon as the pump turns off you can see air bubbles very slowly pop up against the lid. The lid gasket has been replaced and greased two times by me and my pool guy. The lid clamp is extremely tight in that I have to sometimes use my deadblow hammer to loosen it. The lid and clamp are in good shape without any cracks. The pump was recently rebuilt and I took it apart again. All gaskets look good, nothing out of the ordinary. When the pump is off I hear the faintest hiss of air coming from the pump lid area. I can not seem to find the leak. Any suggestions.
Whisperflo Losing Prime
- Thread starter drewcam888
- Start date
Welcome to TFP!
You might want to check out the Pool School article on Suction Side Air Leaks
Any chance your pump was run dry in the past? The basket can deform from the heat and make it difficult to seal.
Just from what you've said, it might be worth a new lid O-ring.
You might want to check out the Pool School article on Suction Side Air Leaks
Any chance your pump was run dry in the past? The basket can deform from the heat and make it difficult to seal.
Just from what you've said, it might be worth a new lid O-ring.
Do you mean basket or lid? I don't see how the internal basket seals anything. I do not believe the pump has ever got hot enough to deform the clear lid. Also from all my inspections it looks to be making a complete seal around the pump lid. I have sprayed water over about all suction joints and valves and have yet to find anything. As stated in the original post I have replaced the lid gasket twice already to try and fix the issue.
If you are losing prime after the pump turns off ... that could be an air leak on the pressure side as well (filter gasket, valve seal, gauge threads). You may not see water leaking out because the pressure causes a good seal, but once the pump is off, it could draw air in and allow the pump to drain.
Although, rereading your post, if you can hear hissing at the pump, then clearly that is the area of the problem.
Although, rereading your post, if you can hear hissing at the pump, then clearly that is the area of the problem.
Meant to say the basket housing, not just the basket.
How high is your pump above the water level in the pool?
Pump is probably 2 feet above water level
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This may be the problem area but i have looked and can't find anything. The noise I am hearing also just might be the bubbles popping against the lid.
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This may be the problem area but i have looked and can't find anything. The noise I am hearing also just might be the bubbles popping against the lid.
Check the drain plugs. They might have a bad O-ring, part 25 on this exploded view: http://www.aquapoolstore.com/pumps/Pentair-WhisperFlo-parts.htm
It could also be the threaded fittings. Or if you have a union somewhere it could be loose or have a bad seal.
It could also be the threaded fittings. Or if you have a union somewhere it could be loose or have a bad seal.
I forgot to mention that the drain plug and o ring were already replaced. The threaded unions on the pump are all covered with silicon and I can't see either of them being the course. I have no unions in the system.
My pool guy replaced them a few months ago and after he tightened them in I siliconed them as an added protection. No bandaid fixes have been done. The previous owner's pool guy really had done an awful job with those connections and the seals/gaskets in the pump. They all were leaking slightly so they had to be redone.
Union fittings should never need anything besides the internal o-ring ... silicone is not going to help and just make a mess.
I was talking about silicone on the threaded NPT ports of the pump housing. I have no unions in my system. Sorry for confusion I misread the statement earlier.
Ah, got it. Well, you should not need silicone on the threaded fittings either is appropriate Teflon paste was used. This is a reason that I do not much care for the threaded fittings since you can not try again easily if it leaks like you can with union fittings.
An air leak can be frustrating but, when you find it, it is usually stunningly simple.
I'm gonna' comment on a few of your statements in your first post..
It sounds a bit like you may be trying to beat this leak into submission and that is not necessary. I would wipe of all that silicone grease and start over with a series of clean, joints. A pic may give us additional insight.
I'm gonna' comment on a few of your statements in your first post..
Look down in top the pump basket and, pump running, tell us where they are coming from......the lid? The drain plug at the bottom of the pump basket?
Take off the O-ring and wipe it clean. Also wipe clean the groove or contact point on the lid as well the pump body. That seal requires very little lubrication. If you are using a deadblow hammer, that's a bit like using a chain saw for brain surgery. A properly seated pump basket lid will snug down quite well with simple hand tightening and, when the pump comes on, it will be further sealed as the vacuum will pull the lid down.
Well, is there reason to believe it stops leaking there when you turn the pump on? Try it and give us a report.
It sounds a bit like you may be trying to beat this leak into submission and that is not necessary. I would wipe of all that silicone grease and start over with a series of clean, joints. A pic may give us additional insight.