Pressure Cooker

[Nick Ostrowski]

Oil fired hot water boiler. Do you think it's safe to say the pressure relief valve is defective? ;)

[Vern Heiler]

Oil fired hot water boiler. Do you think it's safe to say the pressure relief valve is defective? ;)

Looks like about 46 psi. What is the rating on the relief valve?

[Nick Ostrowski]

Looks like about 46 psi. What is the rating on the relief valve?


30 PSI.

[Vern Heiler]

Is it a hot water or low pressure steam system?

[Nick Ostrowski]

Hot water. It needs servicing.

[Benjamin Thompson]

Definately time to get it checked out but I think I have seen more non operational pressure gauges than relief valves.

[Bob Harper]

You can attach your std. hose thread water pressure gauge at the boiler drain and compare with the tricator gauge. If the gauge is correct at 46 psi, then you have two problems: bad pressure relief valve and overfilling the system. If there is an automatic fill valve, then that valve may be defective or someone may have bypassed it.

If the boiler pressure is where it should be then of course, the tricator gauge needs to be replaced.

I would include a recommendation as a boiler plate to the effect annual inspection/ testing and replacement of pressure relief and TPR valves should be labeled on the appliance cabinet right next to the valve.

If there is a diaphragm expansion tank, the tank needs an isolation valve so you can test the air pressure at the Schrader valve and compare with the static system pressure. If water spits out of the Schrader, the diaphragm is blown.

Of course, always check the rating plate to ensure the PV is per mfrs specs. Tall buildings will require a 50 psi system.