Trasformer tripping the secondary control voltage

[atoztech]

I did remember seen one of the leads of the secondary grounded to the chassys of the unit.

As long as its your common on the secondary going to your chassis ground its fine, but make sure its grounded to common. Is this an imediate short on a call for heat or intermittant?

[Mille Racer 69]

If you are referring to the wires from the stat to the outdoor unit, the wire can be any color. Depending on the installer and the number and color of the conductors in the wire they ran they could have used blue for common instead... or anything else they wanted to do.

And it is that installer i am cussing out in my head.
The wires are color coded for a reason.
An installer that does not use the wires as intended
Does not have job security.

[ncboston]

thank you guys for all the inputs, This unit runs good in heat all the way until set point is satisface, then it will tripp the secondary voltage. I did remember seen one of the leads of the secondary grounded to the chassys of the unit.
Would this be the problem.....?
This morning I when back to this unit and remove the thermostat from the base and check the jumper settings, they were all OK, and when I put the thermostat back the system come back ON and star the heating cycle like nothing happen. I be going back tomorrow and remove the ground wire to the secondary.
Thanks for all the inputs

Good Luck.

[airman6290]

If you are tripping the low voltage then you obviously have a short one of the easiest ways to determine which circuit it is in is to isolate each one until it stops tripping. you can do this at the air handler by disconnecting one of the low voltage wires at a time example disconnect the white and cycle it or just use your ampmeter you should be drawing considerably less than 2 amps. If the white isn't the problem try the yellow and agin power up and check amps when you find the problem circuit then check the wiring and any relays in that circuit Darrell

[valdezjc]

Thank you all for your good inputs... i when ahead and replace the defrost card after I was able to recreate the fault.
The fault was cause for the initial call for heat. I should spend more time in trying to recreate the problem...after I replace the board everithing works like a charm.
Thank you again to all!!!

[trey r]

And it is that installer i am cussing out in my head.
The wires are color coded for a reason.
An installer that does not use the wires as intended
Does not have job security.

Why? They are color coded for ease of tracing. For a seasoned tech it is only a pet peeve, not really an issue. I don't know about installers losing their jobs over it.

I had a short in a wall today and used a grey conductor for y.

[bover]

OK, on line voltage to transformer unhooked on one side, big spark or little spark when touch together? Big spark is over 10 amps, will smoke transformer, and indicates a direct short in low voltage wires. Check for goats in back yard (true story).

[DarrinB]

OK, on line voltage to transformer unhooked on one side, big spark or little spark when touch together? Big spark is over 10 amps, will smoke transformer, and indicates a direct short in low voltage wires. Check for goats in back yard (true story).

Or a homeowner with a weedeater.

[Mille Racer 69]

Why? They are color coded for ease of tracing. For a seasoned tech it is only a pet peeve, not really an issue. I don't know about installers losing their jobs over it.

I had a short in a wall today and used a grey conductor for y.

Here is my point*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ *here is where you are


I will just call all the vehicle makers and let them know they don't have to make all their positive battery cables red and negative cables black. They can make them whatever color they want and switch them around whenever they want. Lets see how many extra hours it will take the assembly techs to trace wires to make sure they have the right wires connected and lets see how many componants get fried before they realize that is a terrible idea.

[platchford]

Here is my point*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ *here is where you are


I will just call all the vehicle makers and let them know they don't have to make all their positive battery cables red and negative cables black. They can make them whatever color they want and switch them around whenever they want. Lets see how many extra hours it will take the assembly techs to trace wires to make sure they have the right wires connected and lets see how many componants get fried before they realize that is a terrible idea.

I'm with Trey on this. While I will use certain wire colors on a new install as much as possible, when you do a changeout or find a wire shorted then you have to make do. If the service tech doesn't look at the grey wire on the stat that I had to use for Y then that's his problem. Also, what do you do when you 'need' a blue (or orange) wire but there is no blue (or orange) wire in the thermostat wire? What do you do when you have a two stage furnace with a two stage AC? What do you use for W2 and Y2? There is no standard for this under NEC. Some manufacturers use blue for common... others use black. I don't see what the big deal is.

[Mille Racer 69]

I'm with Trey on this. While I will use certain wire colors on a new install as much as possible, when you do a changeout or find a wire shorted then you have to make do. If the service tech doesn't look at the grey wire on the stat that I had to use for Y then that's his problem. Also, what do you do when you 'need' a blue (or orange) wire but there is no blue (or orange) wire in the thermostat wire? What do you do when you have a two stage furnace with a two stage AC? What do you use for W2 and Y2? There is no standard for this under NEC. Some manufacturers use blue for common... others use black. I don't see what the big deal is.

I am not talking about those situations.
Many times I have found a t stat wire to be grounding out or whatever and will just use a wire that is unused.
I am speaking of new installs or changouts.
If you find red is grounding out and shorting your transformer, use

"X" wire that is just sitting there and not doing anything.
How do you know what red does? Because it SHOULD be uniform
And anybody fresh out of trade school should know what the red wire on a thermostat does. Now if the argument is that how do i know someone else didnt find insulation rubbing away on a wire and just used another color, then I can agree with that. Make sure you look at the terminals. But of the argument is that the color of wire doesnt matter uou can hook it up however you want then screw that. That mindstate is ignorant, arrogant and lazy. Maybe i misread the context of his argument, but i percieved ot as the 2nd one I mentioned. The colors don't matter, just hook it up however you want. I would fire that installer if he didn't change that habbit.

[AC5096]

My wish before I die is, the industry standardize the color coding for control wiring.

It's not really a big deal other than time scratching your butt firguring out what wire goes to what and why the installer was to cheap to run 8 conductor to the condensing unit instead of 5 conductor.

I always ran 8 conductor for a 1 stage cool 2 stage heat HP to the stat and condensing unit just to keep things orderly and simple for the next guy who came along to repair or service the unit.

[platchford]

Mille Racer 69: I understand what you are getting at. I'm totally with you on new installs and as you say, the R should pretty much always be red.

My wish before I die is, the industry standardize the color coding for control wiring.

It's not really a big deal other than time scratching your butt firguring out what wire goes to what and why the installer was to cheap to run 8 conductor to the condensing unit instead of 5 conductor.

I always ran 8 conductor for a 1 stage cool 2 stage heat HP to the stat and condensing unit just to keep things orderly and simple for the next guy who came along to repair or service the unit.

I've felt this way before. Over time it's occurred to me that the problem is different unit configurations would require different wire colors and some of the 5 or 6 conductor wires don't contain the colors 'needed' for a particular job. That being said, with the move to communicating systems perhaps in the future we can have a standard with 4 wires.