Pressure relief valve leaks after zone valve install

eddiedellz

I have a Burnham series 2 boiler where the pressure relief valves seems to start leaking after turn the thermostat off or it reaches itso temptress. I checked the expansion tank pressure 15psi , boiler off pressure is 15 psi aswell. I've shut the thermostat off and watched the pressure climb to 30 psi and start dripping. This is after adding baseboard heat and zone valves to my basement. Any ideas? Thanks!

STEVEusaPA

Air in system, fill valve stuck open, expansion tank now too small with additional radiation. I would start there.
If you make domestic hot water thru an internal coil, the coil may be leaking, pressurizing your system.

rick in Alaska

Make sure you check your air pressure in the expansion tank with the boiler pressure at zero, or you will get a false reading.
Rick

Ironman

Is there a flow check in the circulator or line? If so, remove it.

eddiedellz

> @Ironman said:
> Is there a flow check in the circulator or line? I
I don't see anything after the pump would it be in internal?

STEVEusaPA

I do see the feed coming in right at the back of the circulator. So when the circ comes on, a pressure drop could open the feed valve. If the feed valve doesnt seat properly, it will overfill the boiler. However I don't know where the exp tank is located in relation to the circulator.

eddiedellz

The expansion tank is on top of the circulator pump and feed is T> @STEVEusaPA said:
> I do see the feed coming in right at the back of the circulator. So when the circ comes on, a pressure drop could open the feed valve. If the feed valve doesnt seat properly, it will overfill the boiler. However I don't know where the exp tank is located in relation to the circulator.

The expansion sion tank is on top of the circulator

EBEBRATT-Ed

as @rick in Alaska said you have to check the air pressure in the expansion tank with it removed from the system. It sounds like you have lost your air cushion or that the expansion is too small.

Abracadabra

eddiedellz said:

> @Ironman said:

> Is there a flow check in the circulator or line? I

I don't see anything after the pump would it be in internal?

Pretty sure that's a grundfos pump. There's an internal check on those.

Ironman

Yes, there's an internal check in the discharge side of the pump's volute. It needs to be removed; that's what's causing your problem. You can't use (and don't need) a check valve when you have zone valves.