A DC volt supply is required to operate the Analog Control System. The operating range is 9 to 16 volts DC. If DC voltages are outside the operating range, erratic operation may result.
Use a DC voltmeter to check for the incoming DC voltage between the red positive (+) and the black negative (–) at the connections of the Analog Control Box. If no DC voltage is found, check the supply breaker or fuses.
Check the output DC voltage from the Analog Control Box with the thermostat wires disconnected. This can be done at the Analog Control Box wires listed below.
Check for voltage between the GREEN (GND) wire and:
Tan wire for voltage ranging from 8.38 to
17.31 VDC. Fan terminal on the thermostat.
Blue wire for voltage ranging from 8.38 to 17.31 VDC. High fan terminal on the thermostat.
White wire for voltage ranging from 8.38 to
17.31 VDC. Furnace terminal on the thermostat.
Yellow wire for voltage ranging from 6.73 to 7.53 VDC. Cool terminal on the thermostat
Red/White wire (labeled “TO T-STAT +7.5 SCREW) for voltage ranging from 6.74 to 7.5 VDC. +7.5 terminal on the thermostat.
Orange wire (present only on heat strip or heat pump models) for voltage ranging from 8.38 to 17.31 VDC. HS/HP terminal on the thermostat.
Check for voltage between the BLACK (GND terminal on the thermostat) (Unlabeled) wire and:
Orange wire for voltage ranging from 8.38 to 17.31 VDC. Fan terminal on the thermostat.
Blue wire for voltage ranging from 8.38 to 17.31 VDC. High fan terminal on thermo-
stat.
White wire for voltage ranging from 8.38 to
17.31 VDC. Furnace terminal on the thermostat.
Yellow wire for voltage ranging from 6.73
to 7.53 VDC. Cool terminal on the thermostat.
Red wire (labeled “TO T-STAT +12 SCREW) for voltage ranging from 6.74 to 7.5 VDC.
+12 terminal on the thermostat.
Violet wire (present only on heat strip or
heat pump models) for voltage ranging from 8.38 to 17.31 VDC. HS/HP terminal on the thermostat.
If a furnace is to be operated by the Analog Control System, the furnace thermostat leads are connected to the blue/white striped wires out of the Analog Control Box. The furnace wires can be connected to either wire as polarity is not important. DC voltage is required by the Analog Control Board on one of the two wires for furnace operation.