Help with boiler pressure

Dmelia1

All. Need some insight or advice on my natural gas boiler pressure. I noticed while it is firing to heat it’s very consistent at about 20psi. While hot but idle it rises to about 25psi. Also runs about 25psi if circulating but not firing. This scenario is less consistent as I have noticed it circulate with fire around 20psi. Have never noticed it go aboue 25psi or trip the relief valve. Had it serviced right after we moved in in December and was told everything in good shape. Thoughts?

STEVEusaPA

All the usual suspects. At least it appears to be high and stable.
-Failed/failing expansion tank (or set to wrong pressure)
----or----
-Waterlogged steel expansion tank.
-Fill valve not fully seating, or not set properly.
-Not pumping away.
-Air in system.
-Gauge not working properly.
-Just too much water in the system.

Dmelia1

Thanks Steve! I’m not very familiar with hydronic heat systems. With the weather the way my gut tells me to leave well enough alone right now until it warms up a bit. There is an air scoop with an expansion tank mounted to it below the floor joist above the boiler. Mounted to the air scoop appears to be an automatic bleeder.

STEVEusaPA

Post some pictures, we like pictures. Maybe we can see if you can bleed/purge the system. Do you have column radiators, or baseboard?

If you have an air scoop, and a steel expansion tank, you shouldn't have an automatic bleeder. Maybe your expansion tank is (or getting) water logged.

Could be as simple as a little too much water in the system, combined with the fact that the boiler temp is probably up in the 180°-200° range.

Yeah I wouldn't futz with it unless it blows out the relief valve, or you see the pressure increasing even more (you don't have too far to go before it pops the relief valve).

Everyone is jammed right now and no heat calls have to have priority over "Can someone come out and take a look...?"

Depending on where you are located, should be warming up by Monday.

Your best bet is to find a service provider, unless you like the first one, have them come over, and explain the components and how things work, and how you can do some minimal maintaining of the system-bleeding, purging, visual checking, etc.

Boilers need a little more TLC than furnaces, steam even more.

Dmelia1

Thanks again Steve. Here is more info with pics.

3300 sq ft 2 Story Colonial with indirect 40 gallon water storage tank 3 heat zones 1 zone valve for water tank.

Weil-McLain CGS 5-Installed 2003-In basement

Hot Water Baseboard

DZoro

Can you back up and give us a big picture of the entire system. We then can zoom in on specifics.
Thanks
D

Dmelia1

Lighting is tough. Hope these help