469-1012
Step 1: Prepare for Installation■■Check Table 1 to make sure this thermostat is compatible with your system. If not, return to the
retailer. For more information, call Honeywell Customer Assistance, toll-free 1-800-468-1502.
Table 1. Compatibility Chart.
Not compatible with any 120/240 volt circuit.
aCompatible with 2-wire Honeywell Zone Valves. Isolating relay required for 3-wire thermostats for
zone valves. Not compatible with 2-wire White-Rodgers no. 1361 Valves.
bCompatible with
hot water
baseboard systems. Will not work efficiently on steam or gravity
systems.
System Type Compatible With CT3355
Gas—Standing Pilot Yes
Gas—Electronic Ignition Yes
Gas-Fired Boilers Yes a, b
Gas—Millivolt
No
Oil-Fired Boilers Yes a, b
Oil-Fired Furnace Yes
Electric Furnace Yes
Electric Air Conditioning Yes
Baseboard Electric (120/240 Line Volt)
No
Heat Pumps/Multistage Equipment
No