No Heat? The 10-Minute Emergency Checklist Before You Call

Air Conditioning Filters Guys — best ac and heating repair guys. Need help right now? Call (888) 380-4427, 24 hours a day.

Safety First

If you smell gas, do not touch switches. Leave the house, then call your gas utility from outside, then call us. If a carbon monoxide alarm is sounding, get everyone out and call 911. Everything else on this list can wait until you are safe.

Step 1: Thermostat

Set the mode to HEAT and raise the setpoint five degrees above room temperature. Replace batteries if it is battery powered. A blank screen usually means dead batteries, a tripped float switch on the condensate line, or a blown low-voltage fuse on the control board.

Step 2: Power and Switches

Check the furnace breaker, then find the furnace service switch, which looks like a regular light switch on or near the unit and gets flipped off by accident constantly. Confirm the blower door panel is fully seated, because most furnaces have a door interlock that kills power when it is loose.

Step 3: Filter and Registers

Pull the filter. If it is grey and matted, replace it and try again. Open closed registers. A starved furnace trips its high limit and refuses to run.

Step 4: Gas Supply

Confirm the gas shutoff at the furnace is parallel with the pipe, and check that another gas appliance such as a stove still lights. If nothing gas-fired works, the problem is the utility supply or the meter, not your furnace.

Step 5: Condensate and Drain

High-efficiency furnaces produce acidic condensate. A clogged drain trips a float switch and locks the furnace out. If you see standing water in a pan or a full drain line, clear it and reset.

Step 6: Read the Blink Code

Nearly every modern furnace flashes a diagnostic LED behind the access panel, with the legend printed on the door. Count the blinks and write it down. Telling dispatch "three flashes, pressure switch" gets the right part on the truck the first time.

When It Is a True Emergency

Call for emergency heating repair immediately if indoor temperature is dropping below the mid 50s Fahrenheit, if there are infants, seniors, or anyone with a medical condition in the home, if pipes risk freezing, or if you smell gas or burning. We run 24 hour heating repair every day of the year.

Frequently Asked Questions

How cold is too cold indoors?

Below roughly 60 degrees Fahrenheit becomes a health risk for infants and older adults, and pipes on exterior walls begin to be at risk in the 40s. Do not wait it out overnight in freezing weather.

Should I use space heaters overnight?

Only as short-term backup, one per circuit, never on an extension cord, never unattended, and never near bedding or curtains. Space heaters are a leading cause of home fires.

Will you come out at 3am?

Yes. Our dispatch line is staffed 24 hours. Call (888) 380-4427.

How fast can you arrive?

Typically two to four hours in metro areas, and same-day or next-day in rural areas depending on distance.

Still stuck? Get a technician today

We run 24/7 emergency AC repair and heating repair with flat-rate pricing and same-day or next-day appointments. Call (888) 380-4427 or request service online.