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Honeywell RM7840G1014 jumper JR3

JUGHNE
JUGHNE Member Posts: 11,268
in Thermostats and Controls
Have converted R4140G 1171 to RM7840G 1014 on older steam boiler.

This is operating fine, however the question is to clip JR3 or not?  JR3 refers to Start-up Interlock Check.  The system has 1 pre-ignition interlock consisting of NC main gas valve being closed.  There are 2 running interlocks consisting of air pressure switch in series with aux contacts on 3 phase blower motor contacter.  There are 6 boiler control/limits (2 pressure controller, 2 LWCO's, hi-gas, low gas pressure switches) all must be closed to do start-up. Instructions imply enhanced safety by clipping jumpers.   Is there a reason not to clip JR3, if so why is this even included as an option?  Tech support (not HW) believes it should be cut.  It must be done before 200 hours of operation has passed, after that time frame any cuts produce lockout.

JR1 and JR2 are left intact.
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