CT30 Series • Owner's Manual
1. Match each labeled wire with same letter on terminal.
2. Use a screwdriver to loosen screw terminals, insert
bare wires beneath screws, then tighten screws.
3. Push any excess wire back into the wall opening.
Labels don't match?
If labels do not match letters on thermostat, see table below.
Existing wires CT30/CT33
R • RH • 4 • V
W • W1 • H
Y • Y1 • M
G • F
If this wire is present, you may have purchased the
wrong thermostat. Call 1-800-468-1502 for help.
Set adjustment lever (CT30/CT31 only)
1. Separate cover from thermostat, and remove the insert.
2. Use a pencil to move the adjustment lever to the proper setting
for your system (see table below).
Gas or oil furnace (less than 90% efficiency)
Electric furnace (any type)
High efficiency furnace (more than 90% efficiency)
Hot water system
Gas/oil steam or gravity system
1. Mount thermostat on base and tighten
three mounting screws (CT31 only).
2. Align the 3 tabs on the cover with slots on
the thermostat, then push gently until the
cover snaps into place.
3. Restore power at the heating/cooling
system, or at the fuse/circuit-breaker