check valve

[Notat Home]

Thanks to information from this group, I had installed a gravity powered recirculating loop in my hot water line, with a brass check valve (flapper type) to prevent backflow. It worked very well for years, but now the check valve appears to be stuck in the closed position, preventing circulation, and we have to wait for hot water again.

Is there a good way to fix this valve, short of replacing it? It has a cap on top, but apparently they put that on at the factory so tightly that it cannot be removed. I tried some gentle tapping, then some more vigorous tapping, but that didn't help. I thought of applying heat, but I don't want to undo the soldering.

[trader4]

If it's a cap that's screwed on, using two good size wrenches with one backing up the valve to keep it from twisting should work.

[hrhofmann]

Tap while you're applying the wrenches.

[Steve B]

Investigate changing it using Shark Bites. You will not have to undo the soldering, use any heat, and the Sharkbites work well. You may have to sweat nipples into the valve first, or buy nipples threaded on one end to avoid any sweating on the valve. Make your cuts on the pipe very clean, square and true. If you can get to it with a copper tubing cutter, come down on it very very slowly, giving each tightening a few turns of the cutter afterwards to insure it has cut to its maximum depth. Crunching too far at one time causes deformation or crushing, and then the Shark Bites won't work.

When you do the post mortem on the valve, you will probably see that it is so gunged up that there is nothing other to do than to replace it.

Steve

[DD_BobK]

OP-

Remove the check valve as suggested by Steve B. Soak the check valve & tube assembly in CLR (or equal). I've cleaned malfunctioning check valves like this before.

cheers Bob

[Steve B]

Please let me rewrite this. When using a tubing cutter, of the kind that has a wheel you tighten to make the blade come in contact with the tubing, I meant to write COME DOWN VERY SLOWLY ON THE WHEEL THAT MAKES THE CUTTER BLADE ADVANCE. Get the cutter on the tubing, and tighten it only tight enough to make contact. Then tighten it about half a turn and swing the cutter around about three times in a three sixty. Avoid the impulse to give it any back and forth action, but make complete circles. When you feel the resistance fade, the blade has cut as deep as it is going to. Then tighten up the cutter again just to snug, and repeat with three or four full turns, feeling for when it has cut its maximum depth. Repeat this until it cuts, avoiding the impulse to increase the number of turns on the cutting blade tightener when you think it is about to finish cutting. LET IT CUT UNTIL FINISHED, DOING JUST A LITTLE AT A TIME. Whether you are using Shark bites, compression fittings, sweating, whatever, you will end up with a piece of pipe that will fit better, and need minimal inside reaming or cleaning. Do it slowly, just a little at a time.

There, that's better.

Steve

[Notat Home]

Shark bites is a new term to me. What are they?

[Steve B]

"Notat Home" wrote

It is a brand name for slip on fittings that work like a quick connect on an air hose. I have used them, particularly for a dangerous hard to reach place for sweating in a new piece of burst pipe. They work, and are a cinch to take off. If you can measure and cut straight, they are great. They are spendy, and best for use where it is really hard to get to, or there's a fire hazard. So far no one here has reported a failure that I know of?

Anyone?

Steve