Pennco Natural Gas furnace BANGING

dvs138

I have an intermitten problem with my boiler banging.  It seems to be when the heat is shutting off.  It creates a really loud bang!  Wondering what this could be? HELP!!

Tim McElwain

Is it a mechanical noise

or is it the gas itself shutting off?

dvs138

furnace banging

I'm not sure if it is mechanical. It's not happening on a regular basis so it's been tough to catch.  It happened about a day ago and I noticed the heat had just gone off. Not sure if its the burner??  But it's a really loud bang.

furnacefigher15

Metallic bang?

What can you describe about the bang? metal on metal, etc...

dvs138

furnice banging

I wouldn't say it sounds like metal on metal.  More like someone kicked the side of it really hard.  It's in the basement and it's a little frightening even when I'm in my bedroom on the second floor.

furnacefigher15

Turn it off

And, call a professional right away.



Sounds like this could be a back firing on ignition. Can be potentially dangers.



Your safety is not worth a few dollars in savings. Please at the very least turn it off.

dvs138

banging

I had a zone valve replaced in the off season. could the banging be caused by air in the pipes?

Tim McElwain

What is the

make of Zone Valve, some valves require a correct direction of flow, in other words it could have been installed backwards. In other cases it could be the CV (GPM flow) rating was ignored and the wrong opening on the valve is installed.

furnacefigher15

Not usually

Air does not usually cause banging.



If the valve was put in backwards, I would tend to think it would chatter, or not stay open.



Do me a favor, and while the boiler is off and shut down by a switch, open the boiler and look for any sign of a burnt wire.



If you see anything questionable call a professional.



It's possible you may be hearing a check valve, or a peculiarity with a pump on shutdown, but it's hard to say.