Updated post - initially I thought my whole system was at near zero pressure and was not refilling. Although I'm still not sure they boiler is maintaining correct pressure, I opened the boiler pressure relief valve a few times and now at least there is definitely some refilling going on (via the auto refill line).
I am comparing the boiler's T/P gauge with a new (but somewhat defective) gauge on the return line (a replacement gauge is in route) . The return line is showing ~15 psi. But the T/P gauge on the boiler still shows ~zero when at medium temps and only gets up to around 10 psi at max temp.
Is that T/P gauge probably reading low, or is it normal for the boiler to have a lower pressure than the feed/return line? Or is something possibly seriously wrong in the boiler? It seems to be working fine.
And now of course the relief valve is not seating and there is a pretty steady drip. Any tricks beyond opening and flushing to get it to seat? If not, I think I'll need to call a plumber in as I don't trust my skills to get it replaced and not cause new problems.
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Original Post :
I've recently had a plumber and an HVAC guide out to look over my hydronic system with a Burnham gas fire boiler. The HVAC guy noted that the boiler pressure gauge "wasn't working" but didn't think it was important to fix it. The plumber also seemed uninterested. Since neither has found the time to get back to me, I've been studying up online how I might replace an expansion tank and air vent valves myself. I now realize that when the boiler is hot, the pressure does rise to about 10 lb but is near zero when not firing/ cold. I had ordered a pressure gauge to put onto a drain and double check, but it arrived broken today. Meanwhile I think that the boiler system really is near 0 psi when cold.
.... Irrelevant parts deleted....
I don't see anything that looks like an external low water cut off switch. Would this boiler have one built in? It's a Burnham Spirit series model SP5NH.
I am comparing the boiler's T/P gauge with a new (but somewhat defective) gauge on the return line (a replacement gauge is in route) . The return line is showing ~15 psi. But the T/P gauge on the boiler still shows ~zero when at medium temps and only gets up to around 10 psi at max temp.
Is that T/P gauge probably reading low, or is it normal for the boiler to have a lower pressure than the feed/return line? Or is something possibly seriously wrong in the boiler? It seems to be working fine.
And now of course the relief valve is not seating and there is a pretty steady drip. Any tricks beyond opening and flushing to get it to seat? If not, I think I'll need to call a plumber in as I don't trust my skills to get it replaced and not cause new problems.
===
Original Post :
I've recently had a plumber and an HVAC guide out to look over my hydronic system with a Burnham gas fire boiler. The HVAC guy noted that the boiler pressure gauge "wasn't working" but didn't think it was important to fix it. The plumber also seemed uninterested. Since neither has found the time to get back to me, I've been studying up online how I might replace an expansion tank and air vent valves myself. I now realize that when the boiler is hot, the pressure does rise to about 10 lb but is near zero when not firing/ cold. I had ordered a pressure gauge to put onto a drain and double check, but it arrived broken today. Meanwhile I think that the boiler system really is near 0 psi when cold.
.... Irrelevant parts deleted....
I don't see anything that looks like an external low water cut off switch. Would this boiler have one built in? It's a Burnham Spirit series model SP5NH.
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