Outside Unit not running when set to cool

Old 06-10-20, 05:30 PM
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Outside Unit not running when set to cool

So I just moved into this house and it got warm enough to run the A/C only When i set the T-stat to cool only the indoor fan comes on. The outside unit does not. The outdoor unit is a older lennox while the furnace is a 2019 Tempstar model N8MSN0701412A SERIAL A191914814. I don't know if something got screwed up in the wiring when the new furnace was installed. The outdoor unit runs if I push the contactor in and a voltage meter shows it's not getting 24volts. At the control board on the indoor unit there is a 24 volt transformer that is sending 24 volts into the control board. Where it goes from there I don't know. I have 3 wires at the T stat as shown in the pictures. I only have 3 wires in the wall. I have multiple wires on the board terminal. Which ones send power to the contractor if any?

Thermostat wiring with R and RC jumped(not by me)

Info off the furnace

wiring at the main board inside the furnace

The main board itself

This crazy setup from the power company. I don't know if this has anything to do with it

A brown cable goes from the board and is tied into this

Old 06-10-20, 07:27 PM
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Unwrap the tape and see what is underneath. Cheap/dirty solution might be to put a jumper wire between G and Y on the furnace control board. Otherwise you need to trace wires end to end to figure out what is going to what.
Old 06-10-20, 07:38 PM
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It looks like at thermostat.....
R - red
W - white
Y - black

It looks like a blue on Y on the furnace board.

That box on the outside wall looks like an energy management controller from the POCO. You cannot bypass it if it's on your POCO bill.
Old 06-11-20, 06:26 PM
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Ok did some more investigation. There are no status lights lite on the green box that has a wire going to the A/C. I turned the T-stat to cool the indoor blower came on I went outside and no indicator lights on the box. This is where it gets interesting.I looked at the wiring on the board. I got a brown wire coming out of the furnace that is wired nutted that you see in the picture in post 1. It has a Red wire on C and white on Y.

They are not connected to anything. They were left connected on the board but are just wrapped around the duct. I have a 4 wire that goes up into the ceiling. It is wired as follows on the board, Blue on Y red on R White on W and green on G. Where it goes into the ceiling I don't know. I'm assuming the T-stat. Now This is really strange. I found some wires in a conduit coming up from the floor that do not go to anything. I'm betting that these go to the wires that I found disconnected. I've got pictures.

Info on the outdoor unit


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