Backflow Preventer to a HW Boiler

RobLund

I recently changed out a vent valve on one of the HW radiators. I had to drain part of he system. I turned off the valves on both sides of the BFP and vented the system. After changing the valve I turned the valves back on and vented the system to the highest point, and filled the system. Now the bfp is leaking. Is there an easy remedy?

dopey27177

The BFP may have dirt under check valve seat. Try draining some water out of the system and refill the boiler. Typically a BFP dumps water when the pressure in the boiler and heating system is greater than the pressure on the house side of the domestic water supply.

Jake

RobLund

Thanks.
I will give that a try. I find it interesting that is the cause as there was virtually no flow when taking changing out the vent valve. It makes sense but kind of hard to fathom.

RobLund

The boiler needs to be completely drained? That would be draing the entire system.

STEVEusaPA

If you're draining the boiler, and you have a LWCO, put a ball valve upstream of the WF/BF and one right after. I don't like leaving the water feed open all the time. Check the pressure weekly (if no change in pressure). If you have a leak it will keep feeding.

EBEBRATT-Ed

@RobLund

Make sure the backflow preventer is on the upstream side of your PRV. If not they will act funny and cause problems