69-1638—1 2
MERCURY NOTICE
If you are removing an old thermostat that contains mercury in a sealed tube
(Fig. 1), do not place the old thermostat in the trash. Contact your local waste
management authority for instructions regarding recycling and the proper
disposal of the old thermostat.
Installation

INSTALLATION

Verify You Have Correct Thermostat

Make sure that the CT2800 is the correct thermostat for your heating/cooling system. Read the compatibility chart
below to determine which system you have. If your system is not compatible with the CT2800, the table recommends
an alternate Honeywell model. If you are unsure what type of thermostat is right for your system, visit us on the Web at
www.honeywell.com/yourhome or call Honeywell Customer Care at 1-800-468-1502.
Heating/Cooling System
Compatible
with CT2800? Alternate Model
Conventional
Single stage systems that include warm air furnaces and hot water.
Yes
Electric Baseboard
Electric-powered heating strips located just above the floor, usually 120 to 240
volts.
No CT1950 for 240
volts
M3701
MERCUR
Y
SWITCH
Fig. 1.