Honeywell SUITEPRO TB8575 - Manual (Page 18)

TB6575/TB8575 SUITEPRO™ DIGITAL FAN COIL THERMOSTATS
62-0278—07 18
Both the heating and
cooling equipment are
running at the same
time.
Incorrect System Type
selected.
Check that the Installer Setup code #2 (System Type) value
matches the installed heating and/or cooling equipment.
Heating and cooling wires
are shorted together.
Separate the shorted heating and cooling wires.
Cooling does not turn
on (Cool On is solid in
the display).
Cooling equipment failure. For TB6575A/B/C:
1. Check for 120/240/277 Vac at the equipment between power
and common, (terminals L and N).
2. Check for 120/240/277 Vac between the cool (Y) and com-
mon (N) terminals. If 120/240/277 Vac is present, the ther-
mostat is functional.
For TB8575A:
1. Check for 24 Vac at the equipment on the secondary side of
the transformer between power and common (terminals R
and C).
2. Check for 24 Vac between the cool terminal (Y) and trans-
former common. If 24 Vac is present, the thermostat is func-
tional.
If voltage is present, check the cooling equipment to find the cause
of the problem.
Loose connection or
broken wire between
thermostat and cooling
equipment.
For TB6575A/B/C:
Check for 120/240/277 Vac between the cool (Y) and common
(N) terminals.
For TB8575A:
Check for 24 Vac between the cool terminal (Y) and transformer
common.
If voltage is not present, check the wire connection (loose or
broken) between the thermostat and the cooling equipment.
Fan does not turn on
in a call for Heat.
Wiring or connection
failure
Check wiring and make sure the connection is correct.
Cannot select fan
speed.
Fan Control Type
selection is incorrect.
Check that the Installer Setup code #9 (Fan Control) value is set to
zero (0).
Heating equipment is
running in the Cool
mode.
Incorrect System Type
configured.
Check that the Installer Setup code #2 (System Type) value
matches the installed heating and/or cooling equipment.
Heating equipment
does not turn off and
heat temperature
setting is set below
room temperature
(Heat On is not in the
display).
Incorrect System Type
configured.
Check that the Installer Setup code #2 (System Type) value
matches the installed heating and/or cooling equipment.
Cannot set the system
setting to Heat.
System Type (Installer
Setup code #2) is set to
Cool Only (value = 1).
Set the Installer Setup code #2 value to match the installed heating
and/or cooling equipment.
Cannot set the system
setting to Cool.
System Type (Installer
Setup code #2) is set to
Heat Only (value = 0).
Set the Installer Setup code #2 value to match the installed heating
and/or cooling equipment.
Heat On is not in the
display.
System Type setting is not
set to Heat and/or the
temperature setting is not
set above the room
temperature.
Set the Installer Setup code #2 to Heat and set the temperature
setting above the room temperature.
Cool On is not in the
display.
System Type setting is not
set to Cool and/or the
temperature setting is not
set below the room
temperature.
Set the Installer Setup code #2 to Cool and set the temperature
setting below the room temperature.
Remote sensor does
not display
temperatures
Incorrect IS code. Set the Installer Setup code #4 to Remote (value = 1).
Sensor is not compatible. The remote sensor must be TR21 or compatible 20K NTC.
Table 8. Troubleshooting. (Continued)
Symptom Possible Cause Action