VISIONPRO
®
IAQ TOTAL HOME COMFORT SYSTEM
68-0287—04
36
TROUBLESHOOTING
Table 15. Troubleshooting.
Symptom
Possible Cause
Action
Display does not come on
Thermostat is not being powered
Check if the thermostat is mounted and latched on the wall
plate. If not:
— Mount and latch the thermostat on the wallplate.
Check if the circuit breaker is tripped or the fuse is blown; if
it is:
— Reset the circuit Breaker or replace the fuse.
Check if the power switch at the equipment is in the off
position; if it is:
— Set to the on position.
Check for 24 Vac between terminals 2 and 3 at the
thermostat.
— Replace any broken wires if 24Vac is not present.
— Replace thermostat if 24Vas is present.
Check for 24 Vac between terminals R and C at the
Equipment interface module.
— If 24Vac is not present consult electrician.
— If 24 Vac is Present replace Equipment interface
module.
Temperature setting does not
change
The upper and lower temperature
limits reached
Check temperature setpoints.
Check installer setup Numbers 0600 and 610; modify as
needed.
Keypad is fully locked
Check Installer Setup Number 670 to change keypad
locked options.
Heating or cooling does not
come on and thermostat is not
calling for heat or cool.
Thermostat minimum off timer is
activated
Wait up to 5 minutes for the system to respond (Wait is
displayed on the Thermostat home screen.
System selection is not set to Heat
or Cool
Set system selection to correct setting.
Heating or cooling does not
come on and thermostat is
calling for heat or cool.
Heating or cooling equipment is not
operating
Check Wiring.
Check installer setup number 172 and verify the correct
system type is chosen.
Verify operation of equipment in system test mode.
Heat does not turn on (“Heat On”
is solid in the display)
Heating Equipment failure
Check for 24 Vac at the equipment on the secondary side
of the transformer 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(s) on the
equipment interface Module and transformer common. If
present check heating equipment to find the cause of the
problem.
Loose or broken wire connection
between Equipment Interface
Module and heating equipment.
Check for 24 Vac between the heat terminal(s) on the
HVAC equipment and system transformer common. If
voltage is not present check for loose or broken wires
between the EIM and heating equipment.
Communication is not being
completed
End the call for heat at the thermostat then repeat the call
for heat. Check the communication LED on the EIM board.
— If the LED does not blink, check communication
wiring (wire between terminal 1 on both the EIM
and thermostat.
— If the LED does blinks correctly, check for 24 Vac
between heating terminals on the EIM and the sys-
tem common.
If 24 Vac is not present check the R to Rh connection on
the EIM, if the connection is good replace the EIM.
