Wiring RC840T-120 Relay

Wiring RC840T-120 Relay

The Aube / Honeywell RC840T-120 relay provides two functions:

  1. Provide 24VAC power on the C and W terminals to power a low voltage thermosat
  2. Switch the 120V circuit when triggered by the low voltage R & W terminals

Take care to ensure you are not mixing high and low voltage wiring and that you are connecting to the correct thermostat terminals as needed.

Additionally this device should be installed by a professional and you must ensure that it is installed to any applicable code(s).

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