Cracked Heat Exchanger

CrawlerHero

We occasionally find forced air furnaces that have cracked heat exchangers at work with obvious signs of condensation leaking. Do you immediately red tag and disconnect those furnaces in a case like that even in the winter? Or do you have your boss work up a quote as soon as possible and inform the homeowners of the possible dangers?

HVACNUT

Red tag it.
Shut off the gas or oil supply. Or disconnect and cap it.
Shut off the electric.
Disconnect and a low volt wire or two.
Inform the client and your boss.
Draft, CO, and combustion tests will confirm it and you'll know you did the right thing.
CYA

SuperTech

Yes absolutely shut it down. You don't want to be responsible for the system operating in an unsafe manner

DZoro

Agree with the above, at the same time you need to explain to the HO the serious reasons for your actions. Don't just shut it down and go. They need to understand that death could result if operated further. In those extreme cases they now become #1 priority and usually get changed out that day or the next.
D

Tim McElwain

That is why we need to have some electric heaters in the shop so we can give that customer we shut down some temporary heat until the furnace gets replaced.

STEVEusaPA

I have some thoughts...
Just because you find a crack, is it actually 'unsafe' and must be immediately shut down? I’m not talking about flame rollout, just a discovered crack during a service call.
If combustion is mediocre, and no CO is spilling into the living space, I’d rather inform the homeowner, give them all the info, explain it’s going to get worse, write it up and let them sign it.
I personally don’t have, nor would I lend a customer electric heaters.
By doing so, don’t I assume the liability if their electrical system isn’t capable of handling the load or one of the units is faulty and it starts a fire?
Also we’ve had the discussion here about what’s a proper and legal way to disable a heating system, depending on your jurisdiction. It turns out there’s more liability, again depending on your AHJ, about disabling a furnace at all, and/or properly disabling a furnace.

EBEBRATT-Ed

True that with most cracks with the blower on the air pressure keeps the Co out of the air side so maybe putting the fan on constant is an idea if you choose to run it.

But................it's an ugly situation

CrawlerHero

Thanks for your input. If theres any flame rollout, shut down immediately, I totally agree. Its tough to completely lock someone out in the middle of the winter (freeze up) when theres no readings of CO coming from the supply air but I can visually see something has been going on. I'll have my boss talk to his legal advice, its a tricky situation for me oftentimes.

STEVEusaPA

Of course, have the boss do his due diligence.
The other side of the coin...out by me there is a very large aggressive company, orange trucks, scare/sales oriented.
Basically any furnace over 7 years old has a 'cracked' heat exchanger, and 'dangerous carbon monoxide will leak into your home'.
Of course it needs to be condemned and replaced immediately. They have a fully stocked warehouse of equipment just begging to be sold. And their price is almost 2x over what a good quality company will charge.