Property risk
Heating system failure
A furnace that stops during a cold snap starts a clock, and in an empty house nobody is watching it.
What happens
Furnaces fail in ordinary ways — a failed igniter or flame sensor, a blocked intake or exhaust, a tripped limit switch, a plugged filter causing overheating and lockout, a failed inducer motor, or simply a tripped breaker.
Many failures produce a lockout rather than a dramatic event: the unit shuts down safely and waits for a reset that nobody performs.
Once heat stops, the building cools at a rate set by insulation, air sealing, outdoor temperature and wind. A well-built modern house may lose only a few degrees a day in moderate cold; an older house in a −30 °C wind can approach freezing internally within a day or two.
Blocked high-efficiency intake and exhaust terminations are a specifically Alberta failure. Snow drifts, ice buildup or frost accumulation over a sidewall vent will shut a furnace down, and a vacant house has nobody to clear it.
Why vacancy makes this worse
A heating failure is recoverable if found quickly and catastrophic if not. In an occupied house it is discovered within hours. In a vacant house discovery time equals visit interval, and the consequence is not a cold house but frozen and burst plumbing.
What a visit can observe
- Interior temperature below the thermostat set point
- Furnace not running when it should be
- Error codes or blinking status lights on the unit
- Snow, ice or frost obstructing exterior intake or exhaust terminations
- Tripped breaker on the furnace circuit
- Cold air from registers
Reducing the risk
- Service the heating system before an extended absence rather than after.
- Replace filters before departure — a plugged filter is a common lockout cause.
- Have exterior vent terminations checked and cleared at every winter visit.
- Increase visit frequency during deep cold.
- Keep a licensed HVAC contractor identified in advance, with authorisation for urgent attendance.
- Consider connected temperature monitoring as a supplement to — not a replacement for — physical visits.
Related questions
What temperature should I leave my house at when I go away?
The most commonly recommended minimum for an unoccupied home in a Canadian winter is around 15 °C, though recommendations range from about 13 °C to 18 °C. Some insurance policies specify a figure — if yours does, that number governs, not a general recommendation.
The reasoning behind keeping it that high rather than lower: the thermostat reads the air temperature at one location, usually a hallway on the main floor. Temperatures elsewhere in the building — exterior walls, the basement, above the garage, in a bathroom on a corner — run meaningfully colder. Setting 15 °C at the thermostat may mean 8 °C or lower where the plumbing actually is.
Setting it much lower to save on heating is a poor trade. The savings over a winter are modest; the cost of a single burst supply line is not.
A few practical points. Leave interior doors open so heat circulates. Open cabinet doors under sinks on exterior walls. Keep registers open in every room, including ones you would normally close off. If the property has a smart thermostat, set a floor rather than a schedule, and check that any away mode does not drop below your intended minimum.
And ask your insurer whether your policy specifies a minimum temperature during absences. Several do.
What happens if my furnace fails while I am away?
The building starts cooling at a rate determined by its insulation, air sealing, the outdoor temperature and the wind. A well-built modern house in moderate cold may lose only a few degrees a day. An older house during a −30 °C wind event can approach freezing internally within a day or two.
The consequence is not a cold house — it is frozen plumbing. Once interior temperatures at vulnerable locations reach freezing, supply lines begin to freeze, and the failure typically shows itself when the ice thaws and water starts running.
This is why visit frequency during cold events matters more than visit frequency generally. The difference between finding a heating failure after two days and after two weeks is the difference between a service call and a restoration project.
On a monitored property the sequence is: the failure is found on a visit, documented, you are contacted, and a licensed HVAC contractor is dispatched under whatever authorisation you have set in advance. Setting that authorisation before you leave is what allows it to happen at 8 PM on a Sunday rather than after an email exchange across time zones.
Connected temperature sensors can shorten detection further and are a sensible supplement — though they only tell you something is wrong, and somebody still has to go to the property.
What happens if the power goes out while I am away?
More than people expect, because a surprising amount depends on it. The furnace stops — even a gas furnace needs power for its controls, blower and ignition. The sump pump stops. Freezers thaw. Any connected sensor or camera goes offline, which means you also lose the ability to find out that any of this happened.
In an Alberta winter the furnace is the one that matters. An extended outage during a cold snap produces the same outcome as a heating failure, on the same timeline.
What helps: knowing outages have occurred at all, which a power-loss alert or a smart thermostat going offline will tell you. A generator or battery backup for a sump pump is worth considering on a property with a known water table. And for a long absence, emptying and switching off the freezer removes one whole category of problem.
A visit after any significant local outage is worth booking, because the failures that follow one are often not visible until somebody walks in.
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