My Chromalox HAF-330 electric furnace won't turn on.

[Issa]

Hey,

I have a Chromalox electric furnace, model number HAF-330. Recently the blower fan motor was changed because the old one burned out. The differences in the two motors is that we also had to change our UF(?)S Capacitor to a UF(?)10 Capacitor.

It's been about two weeks now since we've changed it and it has been working fine. Today the furnace just shut off all together. We just tried replacing the transformer but that did not help. Any suggestions?

[Robert]

Check or try the sequencer.



Thanks,
Robert

[Issa]

Hello Robert,

Bare with me through this, it's long.
First, I'd like to say thank you for your timely and helpful response. Unfortunately we still don't have any heat and the furnace is still not working.

I told my father about the sequencer, and we tried checking it:

(a) The resistance in Ohms
(b) We also checked the coils to see if they heated up, and they did. All 6 elements heated up. (I think I'm right relating the elements to the coil?)

Our sequencer has 6 pins, in the same order and spacing below:

3 1

6 5
4 2

Now since we aren't experts in furnace repairs, my father has been looking for someone to repair our furnace before I contacted you. We've had a very difficult time finding someone who repairs an Electric Furnace in Toronto, as most repair Gas. We've had two people in the past 72 hours come in and try and "repair" our furnace. They first just wanted to charge extra money for parts that we bought already and gave us no help. He said he'd call back, no response.

The second guy was helping us over the phone. He finally came over today. Apparently (I was not there) he tested our motor and kept getting 240 volts, then tested again and said it was not working and then tested again and said it was working. We were 100% sure the motor was fine because it was new and hooked up correctly.

Now there is the connecting thermostat Circuit board furnace, letters in the Order:
Y W O C G R
(In this section the 'O' is connected to the 'R' through a wire, aside from that, the thermostat WHITE wire is connected to the 'W' and the BLACK Thermostat wire is connected to the 'O' along with that other wire.)

After he connected his own personal wire from the 'G' terminal directly to one of the pins in a circuit board connected to the main power. I know this is the main because it's connected indirectly to a RED wire which runs in a thick bundle cable to the main fuse box. This bundle also includes a Black wire, also connected to the furnace through a multi-pin circuit board like the Red, and a white wire which is bent and not in use.

Now once he connected this to the Red wire, the motor ran fine, all 240 volts. He then said the motor is fine.

He then proceeded to check the circuits again. There is a switch beneath the sequencer, he flipped it to the next side. Now this is where I'm a bit sketchy on the details. He rearranged some on the wiring from the sequencer to the motor. He then ran the motor and it ran at 110 volts and it strained. The motor began to smell like smoke and my dad said to shut it off, but the guy said let it burn off. My dad shut it off anyways because he didn't want further damage. He then wanted to know if our motor was now destroyed. The guy just kept going on about how our thermostat is a newer model and our wiring is wrong, so he removed the wire he attached and attached a new wire from the 'W' terminal to the 'G' terminal. Ran the motor and said its not running right. The motor did spark every time they ran it. After he said he was done for today, and would have to come back. He wanted $100 for his 'work.' My dad didn't pay him, said he'd pay him next time when it's fixed.

I came home and talked to my dad about a million times trying to figure out what happened. I did notice the switch beneath the sequencer flipped. I left it and flipped the fuse, the motor came on automatically but sparked and seemed like it took up a lot of power because the lights dimmed for a second.

I then flipped the switch back on the sequencer and ran the motor again. It ran fine, no burning, no sparking and no dimming of lights. I removed the wire connecting the 'W' terminal to the 'G'. I tried turning it on and no response.

Also, to let you know, on the circuit descriptions, the wiring is labelled as:

Black = Hi
Yellow=Med-Hi
Red=Low

It's the exact opposite though, with the exception of the Yellow being Low, not Med-Hi.

Now I have a couple questions.

Judging from what I have given as information, do you think that the motor is bad?

Aside from that is there anything I can do to fix it myself, because it's almost been 4 days and my house is freezing and I'm concerned because my family is very cold and I have some pet budgies which lose heat very fast and can get sick.

If I can't fix it, I was wondering if you could suggest anyone within Toronto who can fix our furnace and knows what they are doing?

Thank you very much.

[Robert]

Hi,

Wow, well let me see what I can do. Don't know any Toronto hvac techs.

Lock doors, don't let that idiot back in your house and keep your $100. You may need it to help replace the motor.

IF motor can be made to run fine in any manner, it is ok for now and maybe for good.

However, running a 240vac motor at 120vac only burns off the motor windings and ruins it.

Did I say he was an idiot yet ?


Four things control ALL electric furnaces:

T-stat

Sequencer

Fan Switch (not really needed)

Transformer


From what I "think" you said, LOL, transformer is ok.

Fan switch also or can be bypassed.

So, I would suspect the t-stat or sequencer.


What you believe to be the sequencer is your blower relay and while it can play into blower operation during heating, very rare occurrence.


You will need to try and find a KW rating for your elements.

Also, remove blower housing, look in and down at elements and count the coils.

Should be 2 to 4 coils.


When it first quit, was it just the blower not working or no heat ?


Will not be back on until late torrow evening.


Thanks,
Robert

[Issa]

When the furnace first quit, it was the blower which wouldn't turn on.

The motor coil is burnt. Today I flipped the fuse without the connecting wire the guy had put. ('W' terminal to the 'G'). Nothing happened then all of a sudden a loud bang and a spark. I don't know what cause this, and also I didn't touch any wires or move anything from the night before. (when I had tested it and nothing happened.)

I removed the housing and counted the coils, there are 6 all together. I placed a mirror where the housing was so I could see up and turned on the fuse (the motor was not connected). The first and second coil (farthest from the blower fan) turned on at the same time then shut off. After I waited a couple minutes, and it did the same thing again. I then shut off the fuse. I played around with the wires my dad said that the guy did. When we flipped the switch with the arrangement the guy had, the 5th coil lit up, shut off. Then the 3rd and 4th at the same time on and off. Then the 5th again and it seemed to be repeating this pattern. From what I've heard, the t-stat gets a signal from the circuitry that says the coils are heated and turns on the blower fan? Also I noticed that most of the time the coils heated in pairs (1&2, 3&4) but the 5th only heated, the 6th never came on. Could this be why the fan is not turning on?

Literally just chilling, lol,

Issa

[Robert]

Hi Issa,

With all the wiring modifications and no telling what all done by the handyman at best, it's time for a real hvac tech.

Find someone who is reputable and experienced with mobile homes and hvac.


Trying to DIY at this time is just too dangerous of a fire.



Take care and best wishes,
Robert

[Issa]

Hey Robert,

Actually two days ago my dad called an electrician and the wiring was redone. Basically he just came in, read the circuit diagrams and wired it correctly. With the 6 elements, each was using 5kW and in total 30kW. The motor was wired for a 25kW-240V motor, so it was straining.

It's been running well so far.

Thank you very much for your help. This is also a great site and I'll be using it in the future.

Take care,
Issa

[Robert]

Hi Issa,

That's great, glad it's working. You're very welcome, happy to help.


Thanks,
Robert