Central Electric heat troubleshooting

[chap442]

I have a home with a 5 year old central unit- heat is electric. When I turned on the heat the unit to test before winter --itdoes not seem to be producing maxim heat output. The unit ran for a couple of hours and could not over come a 2 degree rise in temperature.

The differential between room and vent is about 7 degrees- air coming from the vent is warm but appears to not be warm or hot enough to heat the home correctly.


I am fairly handy with a multi meter and have done lots of home repairs- have repaired AC compressor relays/ fans etc but never had to trouble shoot the heating component

where do I start?

[Java_Bob]

check power going to unit, most will be feed of a separate breaker from the fan and control circuit

[chap442]

if I did not have power would I be getting any heat? I am getting some heat - just not enough heat

Shouldn't the differential temp between register and return air be in the 12-18 degree range?

[jnaas2]

Yes the temperature rise should be higher then that. Turn off the power and check the heating coils with a ohm meter first and see if one is burned up. If they all check ok then one of the sequencers is bad. Also a lot of electric furnances have fuses in them for the individual heating elements, check that none are blown

[chap442]

took a quick look last night- it has two circuit breakers on the unit itself- both were ok - neither tripped-- it is a 5 year old unit Lennox- - It is under warranty so I may just give them a call--

[jnaas2]

My first guess is that a heating coil is bad, but let us know what the problem was

[chap442]

problem solved

Repairman out today- he first told me it was the circuit breaker- had moisture and went bad- I did not buy that- but he repaired it and I engaged him in small talk and then asked him to check the heat coming from the vent ( I knew he had not found the root cause) - he then realized there was a real problem- 2 hours later he comes down from the attic and tells me- whoever worked on it last wired it wrong- well guess what - it has never been worked on!- so it must have come from the factory this way or else he did not want to tell me what he really found!-- I now have all 15 K of heat- before I had only the 5 K strip

[HayZee518]

You should have nailed him right there and have him tell you what was wrong. After all you are paying him for the tech call and subsequent repair. I'm curious what was wrong too!

[chap442]

well I did my best to corner him and he insisted the heating strips were wired incorrectly-