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Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 6022
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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I've just installed a Honeywell Series RTH111

Customer Question


I've just installed a Honeywell Series RTH111 non-programmable thermostat, replacing an aging Honeywell programmable thermostat which no longer functions properly. I followed all instructions, and now when turning the heating/cooling power switch back on, absolutely nothing happens - no display at all. The old unit had four wires attached - green, blue, red & white, all matching color connector posts except for the blue wire, which matched up with a "Y" (there was no 'B' post). The new unit has a 'B' post, so I inserted the blue wire into that connector. When turning the power on, nothing happened. So I disconnected the blue wire from the 'B' post and instead connected to the 'Y' post as in the old unit. Turned the power back on, and still nothing. HELP! Must I install a programmable thermometer?

Submitted: 2 years ago.
Category: HVAC