Relief valve didn't open

nick z.

Went out on a dripping relief valve call.The boiler gauge was @ 75 lbs.I stuck a guage on the purge and it read nothing.So I took the cover off the gauge and the snapped the needle back to zero. I looked up at the expansion tank.(old steel type)and the one end of it was swelled out.I drianed the tank whih was logged, and installed a new relief valve.Started boiler back up and checked the press. at the purge, the back off the boilerright by the relief valve, and I ran the press. up and checked the new releif.I thought maybe the boiler waslimed upand the press. wasn't getting to the relief valve.
I have to think with the exp. tank be water logged the press. went up, and the old relief valve didn't open.VERY scary! Makes you want to put a new one every year.

seawood

Use to work in maintance In a factory in there power house and every year when the boilers were shut down for there inspection would replace there relife valves even do it to my home water heater replace once a year Cheap way it from becoming a pile of parts

tim smith

Relief valve maint.

We do annual service on boilers, we flush the relief valve when ever we are out to clear inlet side, this is good general practice.

Matt Undy

I'm guessing this willcure most of the problems with non-working relief vavles. If you open it once or twice a year it won't have a chance to get corroded shut. Since its just a valve held closed by a spring I don't see much room for false negative failure as long as it hasn't coroded shut. Of course i'm sure somone out there at some point has come up with a valve with a part that tends to fall out and wedge it shut when it snaps closed from testing...

I'd be interseted to hear other's oppinion on this.

Matt