[KenLoh]

do you get power on both lines after you reset the trip out switch?

If you are talking about that little reset switch on the fuse, I did try pushing that a couple of times, then tested white-yellow again... No reading.

[KenLoh]

Question: That row of terminals, R,W1,G,C on the far right inside the Air Handler... if there is power on those terminals, shouldn't there be power leading to the thermostat? Does that wire lead to the thermostat?

When I tested those terminals last night, and saw power on them, I immediately went to the wall thermostat, removed the stat cover and tested the wires from the wall. No power there.

[Joshdta]

If you have power on r you should have power to the stat. that reset is supposed to click back into place if it is triped, also it may have a little with mark or red showing it is out.

[KenLoh]

if you have power on r you should have power to the stat. that reset is suposed to click back into place if it is triped, aslo it may have a little with mark or red showing it is out.

Questions:

Does that wire from the air handler (R,W,G,C) lead directly to the thermostat?

If Yes, and If there Is power at R,W,G,C and NO power at thermostat, does that mean there's a problem somewhere along the wire behind the walls??

[Joshdta]

You should have two wires hooked to the board at the air handler. 1 set to the ac unit, and 1 set to the t-stat. and yes it should go directly from the board to the stat. you have power from r to c at the board now? But not at the stat?

[KenLoh]

you should have two wires hooked to the board at the air handler. 1 set to the ac unit, and 1 set to the t-stat. and yes it should go driectly from the board to the stat. you have power from r to c at the board now? but not at the stat?

That is correct. Power at air handler side, no power at wall for thermostat.
Check my pics for clarity.

Do you think I should try putting in a new tstat?

[KISS]

You have 24 VAC and the transformer is good and so is the circuit breaker in your tests.

I'm looking at the pic in post #39. It appears that you have a 3 stage heat and cool of some sort.

There is something fishy with the three reds twisted together and the black wire connected to terminal R. That other thermostat wire going to the outside unit seems connected way wrong.

On the strip:

Jumping R to G should make the fan come on.
Jumping R to W1 should make the heat come on.
W2 and W3 are not connected and this is 2nd and third stage heat.

R and C should have 24 VAC on them. They do, so the tstst should light up

R is either not going to the tstat? It's also black and not red. This raises some real wiring flags.

1. Wrong thermostat - not 3 stage heat
2. The AC contactor coil being wired totally wrong.

Too confused at this point.

[Joshdta]

Not if you have no power at the stat. I would say you have a broken wire somewhere. How many volts are you getting between r and c at the board? 28 volts??

[Joshdta]

If you jump wires at the control board in the air handler does anything work? Fan? outdoor unit? Heat?

[KenLoh]

not if you have no power at the stat. i would say you have a broken wire somewhere. how many volts are you getting between r and c at the board? 28 volts?????

Yes... 26-28V

[KenLoh]

You have 24 VAC and the transformer is good and so is the circuit breaker in your tests.

I'm looking at the pic in post #39. It appears that you have a 3 stage heat and cool of some sort.

There is something fishy with the three reds twisted together and the black wire connected to terminal R. That other thermostat wire going to the outside unit seems connected way wrong.

On the strip:

Jumping R to G should make the fan come on.
Jumping R to W1 should make the heat come on.
W2 and W3 are not connected and this is 2nd and third stage heat.

R and C should have 24 VAC on them. They do, so the tstst should light up

R is either not going to the tstat? It's also black and not red. This raises some real wiring flags.

1. Wrong thermostat - not 3 stage heat
2. The AC contactor coil being wired totally wrong.

Too confused at this point.

It's not likely the issue with the wiring or how it's set up, (although I understand, sometimes things are not set up the way it should be!) as everything has been running fine since I bought the house end of 2002, so the house is about 6-1/2yrs now. This issue just popped up now.

[Joshdta]

You need to check for 28 volts between the 3 buged red wires and C at the board

[KenLoh]

if you jump wires at the control board in the air handler does anything work? fan?, outdoor unit? heat?

Nope... I put the green(G) to black(R)... nothing happened.

[Joshdta]

Is that black tied in with the 3 red? I can not see it from the pic?

[KenLoh]

you need to check for 28 volts between the 3 buged red wires and and C at the board

You mean check for 28V between the 3 red wires in the wirenut, and the blue wire at C?

[Joshdta]

Yes, and where does the black go that is hooked to r on the board, and where doe that blue go that is hooked to r on the board?

[KenLoh]

You mean check for 28V between the 3 red wires in the wirenut, and the blue wire at C?

3 Red wirenutted wires to C shows no power
To G or W1 - same thing - no power

To R - 26V
To W2 or W3 (even though empty) - 26V

[Joshdta]

This is why your stat is not lighting up 1 of the 3 red wires sends power up to the stat, and it has no power. The other one goes to the outdoor unit? Where is the 3rd one going??

[KenLoh]

yes, and where does the black go that is hooked to r on the board, and where doe that blue go that is hooked to r on the board?

The black on R goes into that brown jacket wire. Also on that brown wire, you can see a single red wirenutted to the other 2 reds. Okay, this brown wire with the black and red leads to 2 thin black wires that goes into a white pvc pipe that goes into the ground of the garage floor. I am thinking it leads to the back to the AC condenser.

The blue at the rear row of R, that gets capped (clear plastic cap) with the darker blue that leads to the transformer (red coil).

[Joshdta]

Ok where is the third red wire going? From the wire bug?