New thermostat no heat.
#1
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New thermostat no heat.
My daughter lives in an old mobile home and just recently bought a new thermostat. Going from a mercury thermostat to a smart one with 4 wires. The old thermostat on top and the new Honeywell T4 Pro beneath it. On the old thermostat all my daughter had to do was move the switch from cool to heat and it would heat her trailer. Now, with the new thermostat no heat comes out. The fan blows but no heat, jusylt cold air. It's an old Coleman unit if it helps. And not sure if the jumper from the RC to 4 wire on the old thermostat may be the issue.
Thanks for any Input!

Old Mercury Thermostat

New thermostat.
Thanks for any Input!

Old Mercury Thermostat

New thermostat.
#3
Welcome to the forums.
You posted in the heat pump/electric heat forum.
Is this a gas furnace or A/C with electric heat ?
There may need to be a programming change in the stat.
You posted in the heat pump/electric heat forum.
Is this a gas furnace or A/C with electric heat ?
There may need to be a programming change in the stat.
#5
Is the electric heat large heat strips? or from a "reverse-cycle" AC (AKA Heat-pump) the indoor coil gets hot while the outdoor one get cold the opposite of the function in cool mode. This is important as they have a reversing valve that makes it heat Vs. cool that has to be in the right direction or else you will get cold and not hot air.
#6
Not enough wires for a heat pump. No O/B line
You need to program the stat for electric heat.
200 --> should be already set at 1
205 --> needs to be set for 4 - electric forced air
You need to program the stat for electric heat.
200 --> should be already set at 1
205 --> needs to be set for 4 - electric forced air