Most garage heaters are electric, so look for battery power and connection issues.
Heater Doesn’t Work
There could be several reasons why garage heaters simply aren’t working. Start by checking the heater is properly plugged in and that the breaker on the circuit hasn’t been tripped (or possibly a fuse has blown).
If those are fine, check the thermostat to ensure the temperature isn’t set too low to stop the garage heaters starting up, and that nothing is obstructing the air flow. If there is no problem with these, the problem is likely to be the heating element.
Fan Won’t Run
When the fan won’t run, start by checking the switch to be certain it works. The blades could also be obstructed, or the fan motor might have burned out. This last can be checked with an ohmmeter. If current is reaching the motor but it won’t work, replace the motor.
Fan Works, No Heat
When the fan runs, but the heater produces no heat, look for a defective heating element, or loose wiring. Check the wiring in the heater and solder any loose wires (making sure the heater in unplugged first). When replacing the heating element, be certain that you have an element that has the same rating for voltage and wattage.
Turns On and Off Rapidly
If the garage heater tends to turn rapidly on and off there are two possible causes. The first will be when the flow of air to the unit is blocked, by drapes or something similar. The other likely cause is a problem with the control switch or the thermostat. It’s easy to resolve the first problem, but the second requires you to replace the switch or the thermostat.
Won’t Turn Off
If the garage heater won’t turn off the problem usually isn’t with the heater itself, but with the room. It’s either poorly insulated, or you don’t have a heater that’s large enough for the garage so it needs to keep working. You’ll need to either buy a larger garage heater or improve the insulation in the garage.
A burning smell in a garage heater is worrying and needs to be investigated immediately because of the possibility of fire. Usually the cause will be something like hair or dust on the heating element which is burning.
The garage heater needs to be cleaned. Make sure it’s completely disconnected first. Then open up the garage heater and remove the heating element. Wipe it clean and vacuum out the garage heater to remove all the dust and dirt, so there’s nothing that can burn. Keeping the element clean lengthens its life.