HI! I am trying to install a Hunter Model 42999B Thermostat. I am replacing an old White Rodgers (1F58-58 model). The wires were not labeled and does not correspond to what hunter has. I have green, white, red, yellow, orange, and blue wires. The box has letters of W2, O, G, C, Y. I am now not sure where these went. I went to Lowe's and they told me to correspond the wire color with the new box (which has a G, RH, RC, Y, W). The unit is still not working. Can anyone help? How do I tell what wire goes to what? Thanks!

HI! I am trying to install a Hunter Model 42999B Thermostat. I am replacing an old White Rodgers (1F58-58 model). The wires were not labeled and does not correspond to what hunter has. I have green, white, red, yellow, orange, and blue wires. The box has letters of W2, O, G, C, Y. I am now not sure where these went. I went to Lowes and they told me to correspond the wire color with the new box (which has a G, RH, RC, Y, W). The unit is still not working. Can anyone help? How do I tell what wire goes to what? Thanks!
The rule of thumb is G green, W white, O orange, C blue, Y yellow, R red. If you have RC and RH keep the jumper wire and hook the red to either RC or RH.

The rule of thumb is G green, W white, O orange, C blue, Y yellow, R red. If you have RC and RH keep the jumper wire and hook the red to either RC or RH.

I hooked Green wire to G, W to white, Y to Yellow, but on the new box there is only Rc and Rh with those letters (G,W, Y). I hooked those and O to RC, and Blue to Rh and it isn't working. Any suggestions?

If you have a heat pump you have the wrong thermostat.

Hate to sound stupid, but how would I know if I have a heat pump?

HP: The outside unit functions almost all year round. When the outside temp is too low, the system has an "Emergency heat" mode where heat is usually supplied by electric resistance heaters in the furnace.

Do I have a heat pump is covered in the sticky at the top of the forum along with a complete explanation of the wiring. One big clue is the orange wire connected to the old. Ttop is right, some thermostats won't work with heat pumps. I wish more of the answer here were as good as his.

How do I wire a intertherm split system mobile home furnace and a/c unit?

How do I wire a intertherm split system mobile home furnace and a/c unit?