Coleman Evcon EB12B

[TexTony]

I need some help here. I came home from vacation and my blower wheel was loose and wobbling. The blades came loose from the actually wheel. I replaced it and tried to start up the AC again. Only this time the transformer blew(smoked some then popped).

I've wired everything exactly like the wiring diagram says too and I've blown 2 transformers. The most recent I purchased from you guys. I have no idea what to do here.

On top of that, I have 2 wires coming from the outside unit and I have no idea where they are supposed to go.

Here are some pics.

[Robert]

Hi Tony,

Let me look at pics to see if I spot anything, then will reply again.


Thanks,
Robert

[TexTony]

on a side note, If I remove the wires connected to the LOAD side of the transformer, nothing happens. As soon as I put them back it starts smoking and making the crackling noises(shorting noises).

[Robert]

Where all the wires are wire nutted, the brown sheathed wire coming through side wall of furnace is your t-stat wiring.


The wires they are connected to, are they the wires from the Blend Air control box or do you even have the blend air unit wired up ?


If you could turn off power, use damp cloth to wipe off wires and separate, I could better see what colors and what you have.


Also, you should get several 3 amp plug type automotive fuses and a couple of female terminal wire connectors.


Thanks,
Robert

[Robert]

You'll also need a new transformer, but with fuses and terminal connectors, this will be last one you'll need.



Thanks,
Robert

[Robert]

At top right of load side of xfmr, you have 2 blacks and a yellow or off white colored wire.


Trace the yellow or off white wire and tell me where it goes.



Thanks,
Robert

[Robert]

Do you have an electrical multi-meter to test voltage ?



Thanks,
Robert

[TexTony]

First off, thanks for all of your help so far. It is truly appreciated. I've been without AC for 4 weeks now simply because I was waiting on parts to come in.

Ok, the t-stat wires are all connected to the associated colors.
The top orange wire nut is the yellow which leads to the 2 black wires on the transformer (Load side).
I've check the voltage on the line side to make sure it was correct coming in and it is.

I'm thinking the culprit is the actual sequencer. I think it has a short in it to the black wire(common) which connects directly to the load side of the transformer. I plugged the red wire into the load side and turned the breakers back on and no smoke this time. So the 2 black wires and yeallow wire are causing the short.
I do have a multimeter, what should I check for?

[Robert]

See my above reply about the yellow or off white wire connected at top right on load side.


Where does it go to ?


Unless the wire colors have been changed, you should have 3 blacks to load side of transformer.


Thanks,
Robert

[Robert]

Turn power OFF, disconnect yellow t-stat wire from the yellow it is wire nutted to.


Then tell me where that yellow it is wire nutted goes to.


Also, where does the yell/off white wire at transformer load side go to.


Thanks,
Robert

[Robert]

Transformer:


LOAD SIDE =

Red t-stat wire wire-nutted to red wire connected to power load side terminal.

Common load side has these 3 wires:

Black from blower relay terminal 3
Black from sequencer bottom terminal H1
Black wire-nutted to EITHER one of the wires from outside condenser unit



Then:

Yellow t-stat wire wire-nutted to the other outside condenser unit wire.


Do that AND tell me where the yellow wire that was wire-nutted to yellow t-stat wire goes.


Also, where yellow or off white wire that was connected to load side of transformer goes.


Thanks,
Robert

[Robert]

Any updates ?



Thanks,
Robert

[TexTony]

Sorry, got caught up with work. I will update you in a little bit on this.
Thanks for all of your help so far!

[TexTony]

Turn power OFF, disconnect yellow t-stat wire from the yellow it is wire nutted to.


Then tell me where that yellow it is wire nutted goes to.


Also, where does the yell/off white wire at transformer load side go to.


Thanks,
Robert

Those are actually the same wire.

[TexTony]

Transformer:


LOAD SIDE =

Red t-stat wire wire-nutted to red wire connected to power load side terminal.

Common load side has these 3 wires:

Black from blower relay terminal 3
Black from sequencer bottom terminal H1
Black wire-nutted to EITHER one of the wires from outside condenser unit



Then:

Yellow t-stat wire wire-nutted to the other outside condenser unit wire.


Do that AND tell me where the yellow wire that was wire-nutted to yellow t-stat wire goes.


Also, where yellow or off white wire that was connected to load side of transformer goes.


Thanks,
Robert

Robert I could kiss you for this!!!!!
The outside condeser unit was not wired correctly at those wirenuts. AS soon as I did what you said and turned the power on the UNIT started right up and is running like a champ!!!!

Thank you VERY much. You have a customer for life!