GromTag
Active Member
Right then, the smaller wires are the 24V AC side that lead indoors and the larger wires are the higher voltage side 230V AC that remain at the H/P out side.
An easy way to determine if the wires are correct by previous means (installers or modifiers), when ever it is switched to heating mode check the rails within the furnace when operated after a few minutes to see if they are cold or hot. Caution those finned rails can get quite hot enough to actually cause burns! They should be hot when the H/P is running and thermostat in heating mode.
Also to determine the reversing valves operation by wiring, after the H/P has been off for a bit ( Edit : with the thermostat switched OFF daytime testing would be best as up to 40 minutes can be harsh during night time (it may get too cold indoors with that much time lapsing), 14 minutes is the bare minimum for guesswork testing, 40 minutes are preferred safer as there is no hourly charge theme going on, apply the thermostat temperature higher as to not start the system, then operate the range select switch from cooling to off slowly a few times and determine if the reversing valve is tied to the thermostats function by that switch control. The valve should click with the thermostat switch, On when in cooling mode, off on OFF or heating mode. May need some ears outside, or something to record the sound in remembered tandem with the thermostats switch being changed.
120V models would be rare actually, unless modifications were done, never went that route.
An easy way to determine if the wires are correct by previous means (installers or modifiers), when ever it is switched to heating mode check the rails within the furnace when operated after a few minutes to see if they are cold or hot. Caution those finned rails can get quite hot enough to actually cause burns! They should be hot when the H/P is running and thermostat in heating mode.
Also to determine the reversing valves operation by wiring, after the H/P has been off for a bit ( Edit : with the thermostat switched OFF daytime testing would be best as up to 40 minutes can be harsh during night time (it may get too cold indoors with that much time lapsing), 14 minutes is the bare minimum for guesswork testing, 40 minutes are preferred safer as there is no hourly charge theme going on, apply the thermostat temperature higher as to not start the system, then operate the range select switch from cooling to off slowly a few times and determine if the reversing valve is tied to the thermostats function by that switch control. The valve should click with the thermostat switch, On when in cooling mode, off on OFF or heating mode. May need some ears outside, or something to record the sound in remembered tandem with the thermostats switch being changed.
120V models would be rare actually, unless modifications were done, never went that route.
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