1C20 – Heating Only
1C26 – Heating & Cooling
INSTALLATION AND OPERATION INSTRUCTIONS
FAILURE TO READ AND FOLLOW ALL INSTRUCTIONS CAREFULLY
BEFORE INSTALLING OR OPERATING THIS CONTROL COULD CAUSE
PERSONAL INJURY AND/OR PROPERTY DAMAGE.
Operator: Save these instructions for future use!
2
YOUR THERMOSTAT REPLACES
Description
1C20
1C26
Standard Heating & Cooling Systems - 4 or 5 wires
No
Yes
Standard Heat Only Systems
Yes
Yes
Millivolt Heat Only Systems - Floor or Wall Furnaces
Yes
Yes
Standard Central Air Conditioning
No
Yes
Gas or Oil Heat
Yes
Yes
Electric Furnace
Yes
Yes
Hydronic (Hot Water) Zone Heat - 2 Wires
Yes
Yes
Hydronic (Hot Water) Zone Heat - 3 Wires
No
No
Heat Pump (No Aux or Emergency Heat)
No
Yes
Heat Pump (with Aux or Emergency Heat)
No
No
Baseboard Electric Heating or Line Voltage (120 or 240 Volt)
No
No
MOUNTING SCREWS
