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Wi fi thermostat

jackrutjackrut Posts: 2Member
I have a oil fired hot water baseboard system with two zone valves.
My current t star is only two wire and I can get a new three or four wire into the basement.
I purchased a Sensi t stat and can wire it at the t stat however how do I wire the c wire on the furnace.
Any help will be appreciated.


  • GWGW Posts: 3,530Member
    Most often there’s a C at the heating unit. If you post a pic of the control (where the stat wire connects to your system) you’ll get a fast answer
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    [email protected]
  • GWGW Posts: 3,530Member
    Ahh zone valves—- you have a transformer or a “control” like the Taco ZVC to power the zone valves? You must have a c somewhere to grab if you have zone valves
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    [email protected]
  • Big Ed_4Big Ed_4 Posts: 1,189Member
    The common would be where the two zone vale motors connect to the common of the transformer ... Before you start and add a common wire to the thermostat add a fuse to protect the power source , a 3 amp fuse would be fine . To spade terminals and a 3 amp car fuse would work fine
    I have enough experience to know , that I dont know it all
  • jackrutjackrut Posts: 2Member
    Thanks guys . I'll be back up at the house this week. i'll look for the C terminal at the furnace or zone value. Big Ed I'm assuming a 3 amp inline fuse holder will work on the new c line to the wi fi thermostat ?
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