Honeywell PRO TH4110B Installation Manual page 13

PRO TH41 lOB Programmable Thermostat
[f you have difficulPy with your thermostat, please try the suggestions below. Most
problems
can be corrected
quickly and easii F
Display is blank * Make sure fresh AA alkaline batteries are correcUy installed (see page 7).
Terapetature
settings de net
change
Make sure heating and cooling temperatures are set to acceptable ranges:
o Heat: 40 ° to 90°F (4.5 ° to 32°C).
* Cool: 50 ° to 99°F (10 ° to 37°C).
Heating system
does not respond
("Heat On"
appears on
screen)
Check for 24 Vac at the equipment on the secondary side of the trans-
former between power and common, if voltage is not present, check the
heating equipment to find the cause of the problem.
Check for 24 Vac between the heat terminal (W) and the transformer
common, if 24 Vac is present, the thermostat is functional. Check the
heating equipment to find the cause of the problem.
o Check for loose or broken wires between the thermostat and the heating
equipment.
Cooling system
does not respond
("Coal On"
appears en
screen)
* Check for 24 Vac at the equipment on the secondary side of the trans-
former between power and common, if voltage is not present, check the
cooling equipment to find the cause of the problem
* Check for 24 Vac between the cooling terminal (Y) and the transformer
common, if 24 Vac is present, the thermostat is functional. Check the
cooling system to find the cause of the problem.
* Check for loose or broken wires between the thermostat and the cooling
equipment.
Fen does not
turn on in a
call for heat
_'CooI On" or
"Heat On"
is flashing
"Heat On" is
net displayed
o Make sure the Fan Operation switch is set to the proper system (see page 6).
* Compressor protection timeout is engaged. Wait 5 minutes for the
system to restart safely, without damage to the compressor.
o Set the System switch to Heat, and set the temperature level above the
current room temperature (see page 10).
"Ceel On" is * Set the System switch to Cool, and set the temperature level below the
not displayed current room temperature (see page 10).
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