Discussion Starter · #1 ·
Hello, I'm attempting to install a new thermostat. I understand the new, but the old is not marked with L1, L2, T1, and T2 lines. There are three bundles of wires coming into the box (each one has a white, black, and ground). The bundle on the left has one black wire attached to one black wire on the thermostat. From that same bundle, the white wire is attached to a red. From the the other two bundles, the blacks are twisted together and attached to a black in the thermostat. The whites from this two bundles are twisted together and attached to a red. The grounds are all twisted together. I'm not sure which one(s) go where on the new thermostat. If the old thermostat were marked, it would be much easier for me. Help!