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100 year old hot water boiler and new Sensi thermostat
I have a old coal boiler which was converted to gas with a Honeywell system many years ago. It still works great, but I want to add a new Emerson Sensi thermostat.
The heating system takes over 4 hours of continuous running to get the house warm after it has gotten cold. When we are away for a few days I want to lower the temperature but I want to have the house warm when we decide to come back.
The valve has three terminals that go to the thermostat Red - White - Blue(but the wire is green).
The instructions with the Sensi seem to show that I just add a 24V transformer to the C and the RC terminal - connect W wire to W terminal - connect B(now green) wire to B/O terminal - connect R wire to the remaining RH terminal - and clip the red jump wire on the Sensi.
My concern is that is this all it will take to match up my very old valve control to this nifty new thermostat and will doing this not mess up the system that has worked perfectly for all these years.
I can send photos if it will help.