Page 3 of 6
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Troubleshooting
Equipment Will Not Start
B
1. Check that the thermostat cable wires were not crossed during installation. This may occur
when both thermostat cable wires are the same color or when a spliced thermostat cables
has different colored wires at the thermostat and equipment. Having crossed wires will not
damage the Common Maker or equipment, but will prevent the equipment from running.
2. Some equipment requires an external transformer to be wired into the switching side of
the Common Maker, as shown in diagram ‘E’ in the instructions. Check if this is the correct
wiring by referencing the previous system wiring or the manufacturer’s wiring diagram for
the equipment. If this is not the correct wiring, it may cause damage to the equipment.
3. Connect the Sender’s white wire directly to the thermostat ‘R’ (or ‘Rc’) terminal. This should
activate the equipment. If the equipment activates from this test, the thermostat is not
functioning properly.
4. Using a wire, jumper between the two terminals the Receiver’s red and white wires are
connected to. This should start the equipment. If the equipment does not start from this
test, there may be a problem with the equipment or equipment wiring. If the equipment
does start, proceed to ‘Common Maker Test’ (page 5).
Problem:
The Common Maker and thermostat are installed, the thermostat has power, but the
equipment will not start.
Thermostat
R
C
W
Sender
Purple
Red
Black
White
Black
Purple
White
Thermostat
Cable
W
Heat
R
C
Furnace
24V Transformer
Receiver
Common
Maker
Thermostat
R
C
W
Sender
Purple
Red
Black
White
Black
Purple
White
Thermostat
Cable
W
Heat
R
C
Furnace
24V Transformer
Receiver
Common
Maker
Crossed (Incorrect)
Straight (Correct)
