Hot Water Recirc Pumps and Pressure Balance Valves

[budman]

Have you plumbers run into situations of erratic valve behavior when a one of more pressure balance anti-scald valves are in the loop and the circulating pump is running?

I have heard that the valves don't like the differential in pressure between hot and cold lines.

Thanks in advance.

Tim

[Ned Flanders]

Isn't the idea of a pressure balanceing valve based on diff pressure in lines? I have heard of situations in large buildings where the pressure difference was soo great that the sinks stopped working. I dont remember if it was the hot or cold side that had the higher pressure but that was all that came out of the spout unless you had the knob wayyyy to one side and there was only a hair of any adjustment left. the anti- scald feature is to protect agianst a sudden drop in cold pressure.

What do you mean by erratic valve behavior. Are you sure it is related to the recirc?