If you've lived in Western Montana for a while, you know the pattern. Fall drifts along, and then one week an arctic front drops over the Divide and the overnight lows fall below zero. From Missoula to Hamilton to Polson, that first real cold snap is when heating systems that seemed fine in October start to struggle.
The good news is that most cold-snap breakdowns can be prevented. Here's what to check before the next deep freeze, whether you heat with a gas or propane furnace, a heat pump, or a boiler.
Keep Furnace Vents Clear of Snow and Ice
Many newer high-efficiency furnaces vent through two white PVC pipes on the side of the house: one brings in combustion air and the other carries exhaust out. If drifting snow or ice buries those pipes, the furnace's safety controls can shut it down. That's a good thing for safety, but it's no fun at 2 a.m.
Find your intake and exhaust pipes now, before the snow piles up, so you know where to look.
After a big snowfall or a windy night, check that both openings are clear.
Watch for ice building up around the exhaust in very cold weather.
Never block or cover the vents to "protect" them.
If your furnace keeps shutting off during cold weather and the vents are clear, it's time for a professional look. Learn more about our furnace repair in Missoula.
Watch the Condensate Line
High-efficiency furnaces also make water, which drains through a small condensate line. If that line runs through a cold crawl space or garage, or drains outside, it can freeze during a long cold stretch. When the water can't drain, the furnace may shut itself off. If you notice water around the furnace or a furnace that won't stay running during a deep freeze, call us and we'll track it down.
Give Your Heat Pump Room to Breathe
Heat pumps keep working in cold weather, but the outdoor unit needs airflow. During a cold snap:
Keep snow cleared from around the outdoor unit, and don't let it bury the coil.
Make sure the unit sits high enough off the ground that snowmelt and defrost water can drain away.
Watch for ice or icicles dripping off the roof onto the unit.
Don't panic if you see steam. That's usually the normal defrost cycle.
If your heat pump has backup heat, a cold snap is when it earns its keep. If you're not sure your setup is right for Western Montana winters, see our page on heat pump installation in Missoula.
Check Your Boiler and Hot-Water Heat
Boilers handle cold weather well, but a deep freeze puts every zone to work. Before temperatures drop:
Glance at the pressure gauge and note where it normally sits. A big change is worth a call.
Make sure every zone is heating. A cold zone can mean an air-locked loop or a failed pump or valve.
Pay attention to rooms over unheated spaces or along exterior walls, where hot-water pipes are most at risk of freezing.
For apartment buildings and multi-unit properties, one boiler problem can leave a lot of tenants cold at once, so it pays to have it checked before the coldest weeks. More on our boiler service in Missoula.
Propane Homes: Check the Tank Before the Cold Arrives
If you heat with propane in places like Lolo, Stevensville, or out along the US 12 corridor, check your tank level ahead of a forecasted cold snap. Your furnace or boiler burns more fuel on subzero nights, and delivery schedules can fill up fast when the whole valley gets cold at once.
Smart Thermostat Habits for Subzero Nights
Avoid big temperature setbacks during extreme cold. Letting a house drop a long way overnight means the system has to work hard to catch up, and heat pumps may lean on backup heat to get there.
Replace thermostat batteries if yours uses them.
If you're leaving town, never turn the heat off. Keep it set warm enough to protect your pipes.
Change the Filter
A clogged filter makes any forced-air system work harder, and a cold snap is when it's working hardest. If you can't remember the last time you changed yours, now is a great time.
When to Call for Help
Call a pro if you notice:
A furnace that starts, then shuts off over and over
A burning smell that doesn't go away after the first few runs of the season
Banging, screeching, or grinding noises
A heat pump coated in ice that won't clear
Any zone, room, or floor that won't warm up
A carbon monoxide alarm. Get everyone outside and call 911 first.
We're Here 24/7 When It Gets Cold
Jeremy has more than 10 years of hands-on HVAC experience in Western Montana, and ProCare Climate works on all brands of furnaces, boilers, and heat pumps. We serve homes and businesses in Missoula, Lolo, Frenchtown, Stevensville, Hamilton, Polson, and across Western Montana.
Don't wait for the first subzero night to find out something's wrong. Call ProCare Climate any time, day or night, at 406-546-1289, or request a free install estimate on our website.