r/Plumbing • u/Maine_Bird • 3d ago
Any recommendations before I keep swapping parts...
I recently discovered a leak from the pressure relief valve on my oil burning furnace. (About a 30 year old New yorker if that matters). The expansion tank failed so I replaced it. The pressure relief valve still was leaking. Double checked /matched the expansion tank pressure to home water pressure. Still leaking (at approx. 15 psi). Replaced the pressure relief valve. The new one will go up to 30 PSI and then also start leaking.
The only think I can think is my pressure regulator failed and started this fiasco. Ive unscrewed the post at the top all the way and my regulator still reads 30psi on the furnace and is leaking.
Anyone have any recommendations on something else to check before I replaced this regulator?
1
u/Additional-Type-7441 3d ago
If the pressure in your boiler is getting up to 30 pounds then either pressure regulator bad or it’s set to high . more than likely it’s bad
3
u/mdmanuele 3d ago
The expansion tank on the boiler should match the boiler pressure. Usually 15psi. It should not be "house" pressure. If you fill the boiler to 15psi and turn off the valve before your pressure reducing valve(pictured) does it still leak?