pool filter leak; newbies buying the house need help

[defpool]

We have a contract on a house with a pool. The pool filter was leaking a lot from the top at inspection, and the sellers responded that their pool guy fixed it. Now we're at one week before closing and the filter is leaking again, albeit a small trickle. Their pool guy says it's not a problem.

The seller replied today, "There's a vent screw at the top of the filter in the pictures. It's only finger tight, and occasionally vents small amounts of water. This drips down the side, collects in the mid-line seal and drips down other places. If the buyers don't want to see any water on the filter, they can tighten that screw (it sticks out towards the wall straight behind the pressure gauge at the top of the filter). I'd recommend against that though. When the pump is not running, the filter naturally collects air. If the vent is fully closed and the pump starts, the air stays in the filter and the filter may not fill completely with water. A partly full filter is only partly working. The slightly loose vent screw lets the air escape, making for a fully operational filter."

So. Should a pool filter leak at all? Or do all pool filters leak through their vent screws every day?

Here are some photos from this morning:
http://picasaweb.google.com/defpicasa/PoolFilterLeak?feat=directlink

Thanks very, very much for any advice,

Dianne and Chris, Austin, TX

 

[jparr]

We have a contract on a house with a pool. The pool filter was leaking a lot from the top at inspection, and the sellers responded that their pool guy fixed it. Now we're at one week before closing and the filter is leaking again, albeit a small trickle. Their pool guy says it's not a problem.

The seller replied today, "There's a vent screw at the top of the filter in the pictures. It's only finger tight, and occasionally vents small amounts of water. This drips down the side, collects in the mid-line seal and drips down other places. If the buyers don't want to see any water on the filter, they can tighten that screw (it sticks out towards the wall straight behind the pressure gauge at the top of the filter). I'd recommend against that though. When the pump is not running, the filter naturally collects air. If the vent is fully closed and the pump starts, the air stays in the filter and the filter may not fill completely with water. A partly full filter is only partly working. The slightly loose vent screw lets the air escape, making for a fully operational filter."

So. Should a pool filter leak at all? Or do all pool filters leak through their vent screws every day?

Here are some photos from this morning:
http://picasaweb.google.com/defpicasa/PoolFilterLeak?feat=directlink

Thanks very, very much for any advice,

Dianne and Chris, Austin, TX

What pressure is that filter running at? A severely clogged filter will run at a very high pressure and be more likely to leak than a healthy one.

 

[duraleigh]

It's called a bleed valve. The owner is correct but for the wrong reasons. There shouldn't be air collecting in the filter.

Without getting into too much detail, I would not consider it a deal breaker but I think you will find you have a suction side leak in your sytem that is allowing air to be sucked into the filter. It's reasonably common and, while it can be a PITA to find, it is normally not an expensive fix at all.

In short, I would do the deal but then prepare to find that suction leak and then you can close the bleed valve and keep it closed.

 

[defpool]

Great, thanks, guys. We'll check the pressure tomorrow and report back. We are pretty sure it is a leak, since it is there every time the pump unit is running, not "occasionally."

thanks, Dianne

 

[Peter_S]

Well, a leak is a leak. If it's a slightly open bleed valve it's technically not a leak, IMHO. You really need to close the bleed valve while the pump is running and see if you still have a leak IN YOUR FILTER.

If not, this MAY NOT BE THE END OF YOUR CONCERNS.

If you have a suction side leak as duraleigh suggests, you CANNOT close the bleed valve because you build up air pressure in the filter. With air above the water inside the filter, and the pump starts, you could have a very dangerous situation. Air compresses, and if something gives under compressed air you have an explosive siuation...if stuff breaks, stuff flies around. I hope this is NOT the reason the seller has the valve slightly open.

Just be aware of the possibilities.

 

[duraleigh]

def_pool and Peter_S,

The build up of air pressure is not a likely scenario. About the most psi a pool pump can produce is 35. Virtually all filters are rated @ 50 psi.

Secondly, it is not a closed system where the air or water cannot escape......it can simply go back to the pool through the return lines.

The current owners explanation makes sense but what he is not picking up on is the suction side leak which is causing the air to enter the system in the first place. You could easily confirm that with a visit to the site and ask the owner to shut the bleed valve for you and observe that the leak stops. Left to run, air will build up in the top of the filter and begin to blow out the returns.

Still, as I said above, you will need to track down that suction leak for the system to work perfectly.

 

[danbutter]

Totally agree with duraleigh...there are likely more issues that are leading to this leak. Now the sellers may not be trying to hide this from you...they may not know and just think...oh it drips a little. It took me a couple years and a lot of reading on this site and others to learn how a pool system should work. Still learning actually.

I have heard of buyers demanding a warranty of some sort for the pool equipment. Similar to a home warranty where you pay a $75 deductible and get a new furnace.
If you ask for this though make sure you research your warranty company. We bought our house and then the AC died...we tried to use the home warranty and the company that issued it was gone with everyone's money. What should have cost us $75 because we thought we had a warranty cost us thousands!
If you weren't aware you can also get a pool inspection...like a home inspection, but done by a pool pro.
Good luck!

 

[davemac2]

The vent screw is not usually a relief valve or anything. It's just a manual valve that is opened after re-assembling the filter after it has been cleaned to release any air and get the pump and filter fully primed. For older filters, the o-ring on that vent screw usually degrades from age or from people over-tightening it. So it will leak. You can easily get a replacement for a few dollars. I don't hink you would want to leave it partially open as you could lose your prime on your pump from having the water flow back into the suction line and out to the pool. That would wear out your pump from lack of lubrication and some cavitation because it would be sucking air initially every time it is turned on. If it is truly just a vent screw leak, it is pretty minor and easily fixed.

 

[defpool]

OK, we have contacted four local companies and were able to describe the problem to them thanks you, and all have agreed that it sounds like a suction side leak or some other problem. It's not just supposed to be that way. One offered the pool inspection for $400. And another is willing to inspect for free, hoping to get our business. But it's nice to know we weren't being naive for "not wanting to see water on the filter." Dan, I do agree that the sellers may not know that it's not supposed to be that way. Especially since they use a pool service and their guy says it's not a problem. But then again, they have fought every repair request so far, even a hail damaged roof, so we're a little wary. Interesting thoughts about a warranty on the pool equipment. We have rejected the offer of the home warranty though. We also learned with our current house that just about nothing is actually covered. Kind of a scam, really.

Thanks again to you all. Hopefully all will work out, and we'll be back online here at Pool School.

Dianne