Honeywell CT3400 Thermostat User Manual


 
29 69-0733—3
Troubleshooting Guide
IF… THEN…
Display does not come on. Set the system switch to OFF. Remove batteries. Insert back-
ward for at least five seconds to reset thermostat. Replace
batteries correctly. Display should come on.
Make sure batteries are fresh and installed correctly.
Gently clean battery contacts using a soft pencil eraser. Do not
use anything abrasive on the clips.
Display flashes during You have reached the temperature setting limit. The setting
programming. range is 45°F to 88°F (7°C to 31°C).
Temperature change occurs Check the program times for the period in question. Be sure
at the wrong times. that AM and PM indications are correct. Make sure the current
day and time are correct. Reprogram if necessary.
If you left the thermostat set for Adaptive Intelligent Recovery™,
the start times will occur before your programmed comfort
periods.
30 69-0733—3
Then set the system switch. HEAT: The thermostat controls your heating
system.
OFF: Both the heating and air conditioning
systems are off.
COOL: The thermostat controls your air con-
ditioning system.
HEAT OFF COOL
HEAT OFF COOL
HEAT OFF COOL