Here’s why your high-efficiency furnace might not be the best choice in a cold snap | CBC News
It’s a common occurrence in the middle of a northern cold snap — things don’t work the way they’re supposed to.
Whether it’s vehicles not starting or shifting foundations, northerners have become adept at sorting out weather-related issues.
But what if an appliance is causing issues by working exactly how it’s supposed to?
That’s what happened to CBC North producer Mark Hadlari when his high-efficiency furnace conked out during a recent cold snap, leading him to turn to an expert: Polar Ice Mechanical owner Victor Brazeau, for answers.
High-efficiency furnaces are being embraced around the world as a cost-effective alternative to more traditional models. The furnaces operate at efficiency rates over 90 per cent, emitting steam as exhaust.
That steam, though, can cause issues in chimneys, said Brazeau.
“Icing up is the most common thing that happens,” he said. “You’re utilizing a majority of your heat in the unit itself, so it’s mostly moisture that’s going up through the exhaust. So with temperatures like now, that’s where it wants to ice up.”
As for a remedy, Brazeau suggests — safely — climbing on to your roof and removing the ice, though he says there’s nothing that can permanently fix the issue “unless God wants to give us warmer weather.”
The bright side, cold as it is, is that the only negative outcome is that your furnace will simply shut off.
“They’re sealed units, so it just chokes itself out and shuts down.”
Less efficient, less ice?
If you’re considering installing a new furnace in a cold climate and want to make sure that you don’t have to deal with ice buildup, Brazeau suggests a medium-efficiency furnace over the high efficiency models.
“You’re not utilizing as much of the heat,” he said. “Some of it goes up the exhaust. Some of it’s actually smoke.”
Brazeau also said that having natural gas as an option across the territories, rather than the current reliance on propane, could also provide a solution, though there are no immediate plans for that to happen. Natural gas’ liquefaction point is far colder than propane’s — it won’t liquefy until nearly -250 C, where propane begins to around -44 C — meaning that it could operate with far fewer problems in extreme cold.
“I would love to have natural gas up here … we’d have less issues, and then we wouldn’t have to deal with icing up chimneys,” he said.
But what does Brazeau use at home?
“I prefer to have my oil [furnace].
“Oil burns a little hotter than propane. Less problems.”