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One thermostat controls two zone circulator

I have an oil/hot water heating system which was rewired a few years ago to add a third zone.  Presently one circulator serves only the basement and this works fine.  I have a problem with the other two zones which are served by a second circulator and two Honeywell valves.  APPARENTLY the thermostat/valve that serves the FIRST floor controls the SECOND circulator.  When the SECOND floor thermostat calls for heat the second floor valve will open BUT the circulator will NOT go on UNLESS the first floor thermostat/valve is ALSO calling for heat.  So I cannot get heat on the second floor unless I am at the same time getting heat on the first floor. 

This is a description of the wiring I am able to trace:

The electrical power comes into the system via a wire that goes into a box on the SIDE of the boiler.  Then 2 LINE voltage wires come out of this box along with a LOW voltage wire attached to a transformer mounted on this box.

ONE of the above LINE voltage wire goes to the box mounted in FRONT of the boiler.  The SECOND goes to a box labeled RA832A.  The LOW voltage wire is connected to the wiring of the 2 Honeywell valves.  I cannot determine if it is connected to one or both valves.

From the box in FRONT of the boiler ONE line voltage wire goes to the burner.  The OTHER wire goes to the CIRCULATOR that serves the FIRST and SECOND floor.

Also there is a LOW voltage wire from the FRONT box which is connected to the wires for the TWO Honeywell valves, but I cannot determine if it is connected to only one or both valves.

From the RA832A box there is one LINE voltage wire that goes to the circulator that serves the basement and a LOW voltage wire which is connected to the basement thermostat.

I have been told, not by an electrician, but by a plumber, that the RA832A box needs to be replaced by a different device which will allow both the first and second floor thermostats/valves to each independently control the circulator that serves both the first and second floor.  Is this correct?  Or can the present wiring be “corrected” without new devices or a big bill by an electrician?


  • billtwocase
    billtwocase Member Posts: 2,385
    sounds like

    It may be more of a piping issue than electrical? Post some pics so we can see how the zone valves were installed. The end switch's for the zone valves will tie into "T T" in the switching relay, but is the right pump being powered? Need to see
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