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Problem: Electric furnace heat will not come on or fan blower will not come on.

Problem: Electric heat will not come on or fan blower on the air handler will not come on.

Answer: 1. First and most important, Please make sure your electrical power is turned off before trying to repair or inspect any type of electrical appliance. I would recommend that you purchase an Volt Ohm meter for some of the troubleshooting procedures listed in this section. I always liked to use an amprobe type meter when testing electric furnaces because this type of meter will allow you to clamp around an electric wire, let you see the current and see if the fan or electric heater is working or not. This electric meter will let you see the amps (current) that is being used by a component. Please click here if you would like to see the amprobe type meter that we sell. We have two real good informative YouTube videos that were made by Mark Bower and Grayfurnaceman which show how electric furnaces and sequencers operate. Thanks so much Mr. Bower and grayfurnaceman for making this informative video!

2. Inspect the inside of the air handler or electric furnace for burnt wires. I find burnt wires and connections to be a major problem in electric furnaces. Electric furnaces use lots of electricity. Any connections that are the least bit loose inside the furnace will cause a heat build up, arcing and eventually a completely burned off connection. Before long the entire wire will be burnt off. Please see the picture (compliments from one of our nice customers) below of a burnt heat sequencer. You can see where the heat build up and arcing has caused the terminals to completely burn off the left side! This looks like a two stack sequencer, because of the divisions in the layers of the sequencer:

3. Check your breakers or fuses inside the air handler. Again, make sure your power is off. A good electrical tester multimeter would be nice to test your fuses. Many air handlers have fuses in them like the ones pictured below. You can remove these fuses and test them with a multimeter or if you do not have a multimeter, install new fuses to make sure they have not gone bad.

fuses

4. If you still are not getting electric heat then you should test your sequencers to make sure they are working. I made myself a tester so I could get portable 24 volts without having the furnace power turned on by using an old fan center connected to a junction box with alligator clips attached to the fan center. Please click here if you are interested in a fan center.

Tester made from Fan Center. Son’s 13 Tennis shoe propping up tester.

When 24 volts is applied across the two bottom connections on this sequencer you should get continuity (a closed circuit) between the two terminals the one on the left M1 and the one on the right M2. You should also have continuity between M3 & M4. This might take 30 to 90 seconds after the 24 volts is applied before you get the continuity. You should here a slight click when the contacts inside the sequencer make the connection. If you do not get continuity then you might want to purchase one of the sequencers that we have for sale on the following page: Please click here is you would like to see the sequencers we sell.



Below is the video by Grayfurnaceman on how electric furnaces operate: Thanks Grayfurnaceman!

21 thoughts on “Problem: Electric furnace heat will not come on or fan blower will not come on.

  1. I have a brand new Revolv electric furnace in a mobile home. It has been working fine for about 5 months. It suddenly stopped kicking on. I tested voltage. I changed the thermostat and thermostat wire. I pulled the capacitor and tested it. Nothing seems to be helping. No matter where I set the thermostat it just hums. Please help

    1. Hi Matthew! If the blower motor just sits there and hums, this usually means that you have a bad winding in your blower motor and you will need a new blower motor. I would suggest setting your thermostat to “Fan ON” and testing with a volt meter to see if the motor is getting 220 volts through the two wires that power the blower motor. If you are getting 220 volts and the motor is not running then you know that the blower motor is bad. If you are not getting 220- volts to the blower motor then you will know that you have a bad blower relay or sequencer. Please be careful when working with the high voltage to not ground yourself out. Hope you can easily find and fix the problem. Steve

  2. I have an electric coleman 3500 furnace and a non programabke heat only thermostat. He was working then all of a sudden furnace wont kick on with switches set at auto and heat. If switch is set to on blower comes on amd no jeat even with sqitch turned on to heat. Already cleaned filter, checked drain pan, replaced thermostat. What elese could possibly be tje problem? First time working on furnace not much experience with electric. Thank You.

    1. Hi Brady! This shoulds like you might have a sequencer or blower relay that has gone out and not allowing the furnace blower motor to come on. If you do not know much about electricity and you do not have a volt meter then I would suggest that you call a professional in to troubleshoot because working with electricity can be dangerous. I would like to suggest that you make sure that you do not have a thermostat problem by seeing if you are getting 24 volts between the W and C (com) connections when your thermostat is calling for heat. If you are not getting 24 volts between W and C then you probably have a thermostat problem or a broken thermostat wire problem. I would suggest turning off the power to the electric furnace and making sure all connections are good and tight and make sure you do not have any burnt or loose connections. When I was doing service work many times I would find burnt connections on electric furnaces. Burnt wires are caused by loose connections most of the time. There is a good video on troubleshooting electric furnace sequencers on the following page: https://youtu.be/Q3UXjzDZYek We also have a post and some good videos that I hope will help you out on the following page: https://arnoldservice.com/problem-electric-heat-will-not-come-on-or-fan-will-not-come-on/ I hope you can easily find and fix the problem. Steve

  3. I have a straight heat / cool hvac unit in my modular home if I turn fan to on the blow works but on auto and heat it will not come on its 10kw heat strips. New relay on. What’s your neutral wire gonna be usually in the unit

    1. Hi Bryson! Since you have a 220-volt air handler there usually will be 3 wire cable running into the air handler. Two hot wires which produce 220 volts and one neutral wire. The 220-volt fan motor would run off the two hot wires and usually the neutral wire is not involved with wiring the fan motor. You might have a thermostat problem if your thermostat is set up to run 24 volts through the green wire to turn the blower on in the heating mode, you could have a sequencer problem if the sequencer times the fan to come on after the sequencer is energized from the white (W) wire on the thermostat. Sorry, this is hard to troubleshoot without being there to test with a voltmeter. I hope you can get it fixed soon! Steve

  4. Where are the fuses at?

    1. The low voltage fuse (3 to 5 amp) could be located on the air handler’s control board or the fuses could be located inside the air handler or on the outside of the air handler in a metal box. Some air handlers have high voltage breakers instead of fuses. You should be able to test with a volt meter to see if the fuses or breakers are on. I hope you can easily find and fix the problem. Steve

  5. My Coleman 3400 heats and blows in manual. Heats in auto but fan Doesn’t turn on. I installed new sequencers.

    1. Hi Ken! This is really hard to advise you because electric furnaces are pretty complex with all the wiring. I would suggest making sure that your thermostat is energizing the fan in the auto mode through the green wire. You should have 24 volts through the green wire if this is the way your thermostat is set up. Some of the electric furnaces and sequencers are set for the fan to come on after the electric heaters are energized and are timed for the blower motor to be energized after 15 to 20 seconds the fan is energized through the sequencer. In this set up the fan is not energized through the thermostat except in the air conditioning mode. I am sorry that I can not be of much help. Steve

  6. I have interthrem electric furnace model feh-015ha-03 i replaced the sequncer and the rocker switch before replaced was getting funace to come on fan and heat but wont shut off till pull power off so changed the parts i said and now fan will come on only on the on postion and it wont heat to coils now do i have wires in wrong spot for heating maybe?

    1. Hi Jerry! Without me being there to see and test the sequencer and wires going to the fan motor and coming from your thermostat. I have no idea what your problem could be. Here is a good Youtube video on sequencer testing: https://www.youtube.com/watch?v=Q3UXjzDZYek I hope this helps you find and fix the problem. Sorry that I can not be much help. Steve

      1. steve this is jerry i have gotten an update on my problem i put a new rocker on and auto switch in and a new sequencer i have gotten the fan to kick on byself but the heat strip didnt heat up iam thinking i might have the wires on the wrong prongs on the sequencer wires that come from fuses does it go on gold color and the wires that come from the heat stripes go on the silver prong? that where i feel iam having the problem before i unhhoked old one everything was coming on at sametime but never shut off when i took the old one off it actually fell apart so i know it was bad. here is the model number of the furnace iam working with feh-015ha-03 intertherm

      2. Hi Jerry! Without me being there to see and test the sequencer and wires going to electric heat strips and coming from your breaker box. I am sorry, but I have no idea where the wires go. There should be a wiring diagram in your air handler’s control box to show you where the wires go on the sequencers and electric heat strips. Here is a good Youtube video on sequencer testing: https://www.youtube.com/watch?v=Q3UXjzDZYek There should be plenty of Youtube videos on electric furnace troubleshooting. I hope this helps you find and fix the problem. Sorry that I can not be much help. Steve

  7. My nordine electric furnace heating elements heat up when the thermostat kicks in-but the blower won’t turn on?? But the blower will turn on when switched from auto to on??

    1. Hi Russ! You most certainly do not want the heat coming on in the summer! I would think that you either have a thermostat problem or a sequencer, control board problem. What ever control that controls the fan motor going off an on could be the problem. The green wire and the yellow wire on your thermostat should be energized when the thermostat is calling for cooling. The green wire should turn on the fan motor. If you are not getting 24 to 28 volts AC between the G and Com terminals when your thermostat is calling for cooling then you probably have a thermostat problem. If you are getting 24 volts between G and C and the fan is not turning on then you probably have a sequencer or fan control board problem. Until you get it fixed I would suggest setting the Fan to “ON” so it runs all the time and set the thermostat to cool. Hopefully the outdoor unit will cycle when the thermostat is satisfied. You might want to disconnect the W or W1 wire or turn off your electric heaters so the electric heat does not come on. I hope you can easily find and fix the problem. Steve

  8. Hi Steve! Thanks for sharing this. This is so useful and it’s very informative. I’m sure a lot of people will find your article helpful. Keep on sharing many more useful tips and articles in the future!

  9. Hi my electric furnace the blower works but! It blows cold air what can I do.

    1. I would suggest that you do a search on “How to troubleshoot an electric furnace” using Google. Here is a link to a good electric furnace troubleshooting video: https://www.youtube.com/watch?v=v6BVL2qhRQU More than likely you have a burnt wire inside the electric heater control box, a blown fuse or breaker, a faulty sequencer or a bad heater element. I hope you can easily find and fix the problem so you can have a warm New Year! Steve

  10. I have a Electric air handler my ac and blower motor works but when I turn on the heat I have nothing no blower motor or heat strips I replaced the thermostat when turned on to ac it works but have no heat or blower motor when thermostat is in heat mode

    1. Hi Dennis! Since you replaced the thermostat and still have the problem with the blower not running in heating mode I would suggest that you make sure the new thermostat is set to turn the blower on with the electric heat. Sometimes the thermostats come from the factory and are set to only energize the “G” green blower connection on air conditioning and not in the heat mode. If the new thermostat is set to turn the blower on in the heat mode and it still does not start the blower motor I would suggest turning off the high voltage power to your air handler and trace the wires from your blower motor to see what control, relay or sequencer is used to start the blower motor. After you find the control then I would suggest turning the high voltage power back on being careful not to ground yourself out and get shocked. With the thermostat set for heat see if you are getting 24 volts to the fan relay control from the thermostat. If you are getting 24 volts and the control is not turning on the fan then the control is bad. Most of the time the fan is controlled by a sequencer. You will probably need a new sequencer or fan relay control. I hope you can easily find and fix the problem. Happy Thanksgiving! Steve

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