I've been using a gravity recirc loop (60 ft from tank to last fixture) on my water heater for several years. It worked very well. Bottom of the tank is about 8 ft below the supply & return lines.
I had my 18 yr old gas Rudd tank replaced with a new Bradford White M2XR504 and now my recirc loop no longer works. The Plumber made sure there is no air in the return line. The return line gets hot when the water is used so there doesn't seem to be a blockage anywhere.
There is a swing check valve near the tank drain connection. I confirmed the arrow is pointing towards the tank. A week after tank installation, I removed & drilled a 1/8" hole in the swing plate of the check valve to facilitate flow which is a recommendation I read. That didn't help.
Is there something in the manuf of new tanks (or the tank I have) that might prevent it from working with a gravity loop? I can't figure why else a system that worked well suddenly does not work merely by replacing the tank.
Jon
I had my 18 yr old gas Rudd tank replaced with a new Bradford White M2XR504 and now my recirc loop no longer works. The Plumber made sure there is no air in the return line. The return line gets hot when the water is used so there doesn't seem to be a blockage anywhere.
There is a swing check valve near the tank drain connection. I confirmed the arrow is pointing towards the tank. A week after tank installation, I removed & drilled a 1/8" hole in the swing plate of the check valve to facilitate flow which is a recommendation I read. That didn't help.
Is there something in the manuf of new tanks (or the tank I have) that might prevent it from working with a gravity loop? I can't figure why else a system that worked well suddenly does not work merely by replacing the tank.
Jon