Hello

I bought a Noma Programmable Therm. Model 52-2549-0 and installed it in the winter.

The Furnace worked fine, but now I tried the AC and no go.

I have 4 wires. 1 set in a Green Insulation around a Red and Black wires and the other 2 wires are white and black.

Here is how it is plugged into the noma thermostat

G - Red Wire - Green Insulation one
Y - Black Wire - Green insulation one
Rc/Rh - Black Wire (jumpered)
W/ B/O - White


Any ideas?

Thank you

Do you have any idea where these wires were on the old thermostat? What model is the furnace?

Look at the terminal board in the furnace and determine where the wires from the thermostat go to on th terminal board.
The R terminal should match up with the Rh on the thermostat.
The W terminal should match up with the W on the thermostat.
The G terminal should match up with the G on the thermostat
The Y terminal should match up with the Y on the thermostat.

Also on the Y terminal at the furnace you should have a wire from the compressor.
Also on the C terminal at the furnace you should have a second wire from the compressor.

You can use a OHM meter to find out which wires are which.