Unwanted Heat

JohnCT

I have an oil fired steam boiler with a new trick. The thermostat is off, but few times now the boiler kicks on and sends steam to the radiators and won't shut off until I manually shut it off. Then it won't do it again for a week. Any ideas? Thanks!

Jamie Hall

Does this boiler also heat domestic hot water, either directly (tankless coil) or through an indirect? If so, it is possible that there is an aquastat which is failing.

Otherwise, look around for what can possibly turn the burner on. Check all the safeties -- if the boiler runs regardless of pressure I'd be really worried. You may find an intermittent short circuit.

JohnCT

Thanks, Jamie. Good advice checking anything that could turn the burner on. Turns out mice were chewing on the thermostat wires where they leave the basement into the floor above. The wires look to be 50+ years old with no protective casing. I think the mice crawling around the wires in the middle of the night was then pushing them together which would explain why this seems to happen at 3:00AM. So, I've disconnected the thermostat wires for now so I can keep the boiler on and continue to use the hot water function, and will run new wires through the wall before heating season. Provided the new wire feeds through the 220 year old walls without getting stuck or the old wires breaking in the process, problem solved.

Jamie Hall

Oh joy. Those little critters can be a real pain in the neck. It's why I wire everything -- everything indoors -- with armored (BX) cable!

But you don't need BX for a thermostat wire. That would be overkill. Pulling new wire through can be done provided someone didn't get creative and staple the old wire to something somewhere. I would be very much inclined to attach the old wire -- firmly -- to a narrow (1/8 inch) snake and pull that through first, and then use the snake to pull the new wire back, rather than trying to pull the new wire directly. If it's going along well enough and suddenly snags, don't yank. Pull it back a bit and try, with a helper, to pull at one end and push at the other.

Oh yeah and good luck...

mattmia2

Jamie Hall said:

Oh joy. Those little critters can be a real pain in the neck. It's why I wire everything -- everything indoors -- with armored (BX) cable!

But you don't need BX for a thermostat wire. That would be overkill. Pulling new wire through can be done provided someone didn't get creative and staple the old wire to something somewhere. I would be very much inclined to attach the old wire -- firmly -- to a narrow (1/8 inch) snake and pull that through first, and then use the snake to pull the new wire back, rather than trying to pull the new wire directly. If it's going along well enough and suddenly snags, don't yank. Pull it back a bit and try, with a helper, to pull at one end and push at the other.

Oh yeah and good luck...

I would use string, preferably pull sting or something similar instead of a fish tape. I'd pull a second piece with the wire and leave it there for future use in case you needed to add another cable some day.

EBEBRATT-Ed

Mason twine is the best. Stuff is pretty strong

BobC

As said those little critters can cause mayhem if not kept under control. In the old days the family cat kept them fearful enough to limit their damage.

Australia had a program to cull it's population of stray and feral cats a while back and it was so successful they are now over run with mice. Chicago got it's rat problem down to manageable proportions by doling out feral cats to infested areas. I once lived next to a large marsh, some complained about rats in their homes, I just had to put the bodies at my doorstep into the trash, the cats i had thought it was great sport. They ate all the mice they caught but wouldn't eat the rats - that was my fault because I fed them cat food.

JohnCT

BobC said:

As said those little critters can cause mayhem if not kept under control. In the old days the family cat kept them fearful enough to limit their damage.

Australia had a program to cull it's population of stray and feral cats a while back and it was so successful they are now over run with mice. Chicago got it's rat problem down to manageable proportions by doling out feral cats to infested areas. I once lived next to a large marsh, some complained about rats in their homes, I just had to put the bodies at my doorstep into the trash, the cats i had thought it was great sport. They ate all the mice they caught but wouldn't eat the rats - that was my fault because I fed them cat food.

Yeah--my cats are pretty good at keeping mice out the house, but pretty worthless when it comes to patrolling the basement. If I catch a mouse in a trap, they will bring it upstairs to try to take credit for it--trap and all.