If your electric heater furnace is not providing heat anymore, follow these steps to troubleshoot and fix the problem.
Electric Heater Furnace Troubleshooting
Step 1- Check for the obvious stuff first.
Before diving into more complicated/pricier areas, check for some obvious stuff first. Check to be sure the circuit breaker has not tripped at the service panel. Now check if your electric furnace has a fuse. If it does, is the fuse blown? Also, be sure the thermostat is still set at the desired level as someone may have adjusted it. Other things to check are the cold air inlet filter and blower outlet for blockage.
Step 2- Disconnect power at the service panel.
Shut off the breaker to the electric heater at the breaker panel. Use your multimeter set to the correct voltage and test for power at the input connections to the heater. Do not move on until you are sure the circuit is dead.
Step 3- Check the electric furnace wiring and connections.
Closely inspect all exposed wiring for fraying, burning, or breaks. After long periods of time, wiring may become old and brittle which leads to shorting and breaks. If the breaker was tripped, then there is a good chance that there is a short along the wiring somewhere. If all the wires check good, inspect the wire connections for looseness or corrosion. If faulty wiring is found, follow this wire repair guide to correct the problem.
Step 4- Check the blower motor and belt.
The easiest way to know if the blower motor is functioning is to listen for the motor spinning up during operation. Temporarily turn power back on to the furnace once everything you may have disconnected in previous steps is reconnected. Listen carefully for the blower motor to spin up, which should be obvious. Also, if you have any air coming out of the heater ducts, then the blower is operating as advertised.
If the blower is not producing airflow, the easiest thing to check is the blower belt. Shut off the power to the furnace again at the breaker service panel. Visually inspect the blower belt for signs of wear, fraying, or breakage. Replace the worn or broken blower belt.
If the belt is good, but the blower still does not operate, then the motor may be faulty. To test yourself, follow this motor troubleshooting guide.
Step 5- Check the heating elements.
If you find blowing cold air in step 4, then a likely problem is a faulty heating element. Most electric furnace heaters utilize three separate heating elements in the form of coils. The furnace uses a sequencing relay to power up certain heater coils at different times. Shut power to the heater off at the service panel and visually check the heater coils for damage or breaks. Never touch the coil metal with your hands as you can be shocked and/or burned. Inspect with your eyes.
If you find a damaged heater coil, you have a few options. Either call a service technician to replace the defective heater coil element, or remove it and bring to a qualified technician for repair. Most times a defective element will need replacement. If the heater element cannot be removed, then a complete appliance replacement may be necessary.