We recently replaced an old thermostat with a programmable thermostat, and now the heat won't kick on. My husband said he switched the wires directly over, and the AC works fine. But when we switch to heat we can hear the unit turn on, but the fan doesn't turn on or blow out anything. This is a manufactured home, built 9 years ago. The wires coming from the wall are red, white, yellow and green. The thermostat has 5 connections, Rh, Rc, W, Y, G, with the Rh and Rc connected by a jumper. They're currently connected by color, and again, the AC works, but we have no heat. Any thoughts?