Robertshaw RS10420T Installation Manual page 9

WIRING
Notes
Wire Specifications
Use 18- to 22-gauge thermostat wire.
Shielded wire is not required.
Emergency Heat Operation:
In many heat pump systems with no
emergency heat relay, a jumper can
be installed between E and W2 to turn
thermostat into a single stage control
for Emergency Heat Operation.
Float Switches:
A float switch or similar device
which breaks the control wire (Y) not
the power (R) should be installed.
Interrupting the power circuit will
shut off the power to the thermostat
completely and stop it from operating.
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