Background: I removed an in line wall heater thermostat from a 120v outlet, and want to ensure I reconnect the wires accurately.

Question: A google search hit insists the wire marked in red is running from the the panel, and if tested should be active if circuit is on, and should connect to the "L1", the other wire black and not labeled runs to the heater and connected to the "T1". Is this accruate? Is testing the connection with circuit on necessary? Out of curiosity, do the characters stand for anything?

enter image description here

  • Can you post a photo looking into the back of the box? – ThreePhaseEel Nov 4 '16 at 22:24
  • outlet or thermostat product box? – user289394 Nov 4 '16 at 22:33
  • The outlet box, although a photo of the thermostat's backside might be helpful too – ThreePhaseEel Nov 4 '16 at 22:37
  • The outlet box seems like it's screwed in from the back and doesn't seem worth the effort to remove for this project. – user289394 Nov 4 '16 at 22:43
  • Finally found a manual, step 3 has a diagram that provides detail that T1 connects to heater. – user289394 Nov 4 '16 at 22:45

L is for line or supply. T is for load. Basically L is power in and T is power out.

If you are trying to find which wire is coming from the panel, yes the power must be on. The one from the panel will show voltage. Which I assume will be the one marked with red tape.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.