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canuk
Re: A/C unit not working..

Did the orginal wire setup have only 4 wires hooked up?

BigWalt
Re: A/C unit not working..
canuk wrote:

Did the orginal wire setup have only 4 wires hooked up?

yes, red, blue, green and white.

I did remove the thermostat, it only has 4 wires.

JLMCDANIEL
Re: A/C unit not working..

On the heat pump did you have a "Y" terminal? On some heat pumps you have to have a jumper from "Y" to "W".
Jack

canuk
Re: A/C unit not working..

which wires go to which terminal on the thermostat ?

BigWalt
Re: A/C unit not working..
JLMCDANIEL wrote:

On the heat pump did you have a "Y" terminal? On some heat pumps you have to have a jumper from "Y" to "W".
Jack

on thermostat itself.....
yes, there is Y and W terminal but no jumper...
let me take pictures of thermstat and post here within 10 minutes.

FYI.... I did not replace entire length of thermostat wiring.
Just the junction connection outside to inside of A/C / heater circuit board.

JLMCDANIEL
Re: A/C unit not working..

Is there a "Y" on the heat pump?
Jack

BigWalt
Re: A/C unit not working..
BigWalt
Re: A/C unit not working..
JLMCDANIEL wrote:

Is there a "Y" on the heat pump?
Jack

I have to go outside during the day.....right now it is raining like MOFO....:mad:

question.......
Is there outside thermostat that prevent heat pump coming on?

JLMCDANIEL
Re: A/C unit not working..

I'm going to take a quess here , Red is 24 vac, G is fan, W is heat, and your Blue is cool. The thermostat mearly closes a switch and connect Red to White for heat, Red to Green for the blower motor, and Red to Blue for cooling. So when the cooling is on you should have 24vac on the Green to turn on the blower and on the Blue to turn on the cooling. When you call for heat you should have 24 vac on the Green and the White. Usually Yellow is used for cooling but in your case it seems that Blue was used..
Jack

canuk
Re: A/C unit not working..

This type of thermostat is straight forward .... the mercury bulb makes the connection based on the mode ... heat/cool.

Set the mode to heat .....you should be able to jump the RC to W that should engage the heat .

If it doesn't then there's somthing else further down that causing a problem.

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