Emergency Furnace Repair

The thermostat: confirm it is set to Heat rather than Auto or Cool, that the setpoint is above the current room temperature, and that the display is lit. Battery-powered thermostats die silently, and a dead thermostat looks exactly like a dead furnace. If it is a smart thermostat, check that it has not lost its C-wire power and dropped into a low-battery state.

The power and the door: furnaces have a dedicated breaker and, at the equipment, a service switch that looks like a light switch and gets flipped off by anyone who has been in the attic or closet. Most furnaces also have a door interlock switch that prevents operation if the blower panel is not seated. A panel put back crooked after a filter change will stop the unit cold.

The filter: a filter packed solid will trip the high limit and shut the burner down within minutes of starting. Pull it. If it is grey and matted, run the system without it temporarily and see whether the heat stays on. If it does, you found the problem and you need a filter, not an emergency visit.

Call immediately, at any hour, for a gas odor, a carbon monoxide detector alarm, visible scorching or soot around the furnace cabinet, a burning electrical smell, or a total loss of heat during a freeze warning with vulnerable occupants in the home. Those are safety events, not comfort events.

Also call right away for a furnace that ignites with a delayed whoomph rather than a smooth light. Delayed ignition means gas is pooling in the burner compartment before the flame arrives, and it can escalate.

It can generally wait for a normal appointment when one zone of a multi-zone home is cold, when heat is weak but present, when the furnace runs but cycles more than you would like, or when the outdoor temperature will stay in the 50s or above. We would rather book you a real appointment window tomorrow than charge you for tonight when nothing is at risk.

Safety first: on any gas furnace we check for combustion spillage, verify the venting is intact and clear, and confirm the heat exchanger is not compromised before we make the unit run. Restoring heat by ignoring a safety condition is not restoring heat.

Then we run the ignition sequence and measure through it — igniter resistance, flame-sensor output, pressure switch against actual draft, gas pressure, blower amp draw — so the fault is identified rather than guessed at midnight. Our trucks carry the parts that fail here: igniters, flame sensors, pressure switches, capacitors, limit switches, sequencers, and common control boards.

Most emergency calls end with heat restored on the same visit. When a part has to be ordered or the unit is genuinely unsafe to operate, we tell you plainly, help you set up safe temporary heating, and get the permanent repair or replacement scheduled at the front of the queue rather than the back.

Consolidate into one or two rooms, close the doors, and close off unused rooms. Keep interior doors to those rooms shut and use blankets rather than trying to heat the whole house with space heaters. Plug space heaters directly into wall outlets, never into extension cords or power strips, and keep three feet of clearance on all sides.

Never use a gas range, oven, grill, or a generator indoors for heat. That is the single most common cause of carbon monoxide poisoning during cold-weather outages, and Valley homes are tight enough for it to become dangerous quickly.

Open curtains on south-facing windows during the day to pick up solar gain, and close them at dusk. If a hard freeze is forecast and the home will be unheated, let a faucet drip and open cabinet doors under sinks on exterior walls.