Search results

  1. C

    Second controller in parallel with a Honeywell ST9400?

    Greetings, experts. Is it possible to bypass a Honeywell ST9400 programmer by applying 240V to the appropriate output (pin 4) without blowing it up? This is in a rented house with TRVs but no room thermostat. I'd like to be able to control the heating remotely, preferably without disturbing the...
Back
Top