Honeywell Chronotherm III User Manual page 20

IF. . .
Display will not come on.
Display flashes during programming. a YOU have reached the temperature setting limit The setting range is
Program is lost due
to power outage.
Temperature change occurs
at the wrong times.
Heating will not come on.
Cooling will not come on.
The building is too
warm or too cool.
Display says HEAT ON or system
light is on, but no heat is coming
from the registers.
Display flashes REPL BAT or goes
blank when power is turned off.
THEN. . .
replace with fresh ones.
Make sure thermostat is correctly mounted on base.
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45°F to 88°F. In models with automatic heat-cool changeover, the
COOL temperature setting must be at least 3°F above the HEAT
temperature setting.
. Programming has been lost because of a power outage. You must
reprogram.
. Check that backup batteries are installed correctly. Replace if
necessary. Reprogram the thermostat
. Check the program times for the period in question. Be sure that
AM and PM indications are correct Make sure the current day and
time are correct Reprogram if necessary.
. Rememberthatthe heating equipmentorairconditionercomeson
before the MORNINGS and EVENING start times so the house will
be at the desired temperature when the period starts.
Checkthefuseorcircuitbreakerand replaceorresetif necessary.
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Check that switch on thermostat is set to HEAT or AUTO.
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Heatpumpthermostatshaveabuilt-in timedelay which may ad d to
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time delays in the heating equipment. Allow up to 10 minutes after
changing the setting before the compressor starts.
. If temperature setting is higher than current temperature, and
and air conditioning contractor.
. Check thefuseor circuit breaker
. Check that switch on thermostat is set to COOL or AUTO.
. The thermostat has a built-in time delay, which may add to time
delays in the cooling equipment Allow up to 10 minutes after
changing the setting before the air conditioner starts.
If temperature setting is lower than current temperature, and
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and air conditioning contractor.
setting.
. If desired, change the time or temperature setting. See page 21.
. Allowtimefortheheating equipmenttoheatupand thefan to come
on before checking for heat at the register.
. Install fresh alkaline batteries.
and
replaceor reset if necessary.