I just bought a Noma, model no.52-2570-6 programmable thermostat and I am having trouble installing. The original manual thermostat has five(5) wires, green, orange, white, red, and black. The black is not connected to anything at all. The white wire is connected to the terminal marked Y on the old thermostat, the orange wire is connected to the terminal marked G, the green wire is connected to the terminal marked A and the red wire is connected to terminal marked A. Actually the red wire is connected to 2 terminal, one is marked A and the other one is marked nothing. The new thermostat terminal are marked differently (Y, Rc & Rh (these 2 terminal have a little metal piece connected as if they were one), W-O/B , G , H2, H1. Somebody, please help.

Thank you.

Before you disconnect or change anything I thought I would mention you have nonstandard color code wiring and this can cause a major nightmear for someone not in the heating trade.

First of all you have purchased a heat pump thermostat. Do you have a heat pump system?

What is the exact brand and model number of the old thermostat?

If you have your heart set on a new thermostat just remember what you might get yourself into with this wiring problem.