10 guides
No heat or no cooling: what to do
What to check before you call anyone, what to do about a gas smell or a carbon monoxide alarm, and how to keep a house and its pipes safe until someone comes.
It has stopped, or something smells wrong
Gas and carbon monoxide first, then what to check yourself.
- No heat in a freeze Protect the pipes first and the people second, because you can add layers and the plumbing cannot. Open cabinet doors, let faucets drip, and close off rooms you are not using while you wait for someone.
- You can smell gas Leave the building now. Do not switch anything on or off, do not use your phone inside, and do not look for the leak. Call the gas utility from outside, from a neighbor's, or from the street.
- The CO alarm went off Get everyone outside into fresh air and call emergency services. Do not open windows first and do not look for the source. Carbon monoxide has no smell and confusion is one of its symptoms, which is why the rule is leave, not investigate.
- The furnace will not start Thermostat batteries, the breaker, the switch that looks like a light switch, and the filter. Those four account for a large share of no heat service calls, and all four take ten minutes.
- No cooling in a heatwave Get the house closed up and shaded before the day heats it, and get vulnerable people somewhere cool. Then check the filter, the breaker, and whether the outdoor coil is blocked, which is most of what fails.
- Ice on the air conditioner Switch the cooling off and run the fan only until it thaws, which takes hours not minutes. Then change the filter. Ice on an air conditioner always means airflow or refrigerant, and running it iced damages the compressor.
Getting through until someone comes
Keeping the house and the pipes safe without making it worse.
- Getting through without heat Protect the plumbing first, then heat one room rather than the whole house. Never a stove, a grill, or an unvented heater, and one electric heater per circuit plugged straight into the wall.
- Space heater safety Straight into a wall outlet, never an extension cord, one per circuit, three feet of clear space, and off when you leave the room. Portable heaters cause a large share of home heating fires every winter.
Insurance and cost
What a policy does with a failed system, and what the work costs.
- Does insurance cover it? Almost never for the unit itself, which is treated as wear. It covers the damage a failure causes, and a separate equipment breakdown endorsement or a home warranty is what covers the equipment.
- What HVAC work costs Ask what the service call is, whether diagnosis is separate, and whether it is credited against the work. Then ask the question that decides everything: how old is the system, and is this repair worth making.