: I have a hot water baseboard heating system. I recently replaced a section of BB during a remodeling project. Afterwards I purged the system and turned on the boiler. At that time the pressure in the system when up very high and the t&p valve released. After it released it seemed to be working OK. The pressure would be around 20 psi @ 180 F when running. That was a few weeks back. Last night I notice that the t&p must have released again since there was water on the floor and the pipe from the valve was dripping. I put a bucket underneath and it had an inch or two of water in it this morning. What could be causing this? The system has a PRV, backflow preventer and expansion tank which I installed a couple years ago.
I just want to clarify the following which I'm sure you already know. The t&p valve I'm talking about is really just a pressure relief valve (set @ 30 psi) and the PRV is the boiler feed valve which I believe is factory set at 12 psi and has the handle to overide which I did not use when doing the purge.