I have 2 baseboard heaters currently connected to a rotary thermostat. I am replacing the thermostat with a programmable digital thermostat which can be wired either as single pole (L1 only) or double pole (L1 and L2). There were 2 black wires from the load and 2 red wires from the line in the wiring diagram for the existing installation. I assumed the 2 black wires were L1 and L2 so I connected them to the matching L1 and L2 wires on the new thermostat, a Lux ELV4 model (The old rotary thermostat was a TPI TR202-1/TW242 model).
The installation worked, but I noticed that the room is always hot. The actual reading is 73 degrees no matter how low I set the thermostat. Apparently, only one heater is cycling or switching on and off while the other heater is on all the time. It seems to me that I should have wired it only as single pole (L1 only) and just left the second black wire disconnected. The instructions for the new thermostat say that only L1 is switched during normal operation.
But then, doesn't that mean that only 1 baseboard heater is connected? How do I connect the wires so that my single thermostat will control the 2 heaters?
Thanks foe any help.