Condensation Leak on High-Efficiency Furnace: Seal or Don’t Seal?
LESLIE: Jean in Iowa has a question about her heating-and-cooling system. Tell us what’s going on at your money pit.
JEAN: I have a high-efficiency furnace with the PVC pipe that comes out for the intake and the exhaust. And at the first joint – it’s about a 45-degree angle. And we noticed that that joint wasn’t totally sealed. But our question is – we noticed that there was condensation dripping out of that joint. So if we seal it, will that condensation go into our furnace and cause damage? We’re not sure what we should do with it.
TOM: How old is this furnace?
JEAN: Five years.
TOM: What’s the efficiency of the furnace?
JEAN: In the 90s.
TOM: I ask you this because some furnaces are designed to trap the condensation and pump it out. And so if you have a condensing furnace, then that might not be as much of an issue.
Because what happens with those high-efficiency gas furnaces is they put the exhaust gases out at such a low temperature, that they quickly turn from gas back to water. And then the moisture drains back through the vent pipe, gets caught by a condensate system and then pumped out.
So have you had it serviced this winter yet?
JEAN: Not this winter.
TOM: Yeah, you really need to do it every year because the fact that the gas burns, it burns dirty and then you get combustion deposits on the burners. And then they can become inefficient. They’re wasting money and potentially be dangerous. So, I would address this with the service contractor when he comes out to do your service, which you’re going to call for tomorrow, OK? You want to make sure you get that done because it’s important, every winter, to have a heating system serviced.
JEAN: OK. Thank you.