Troubleshooting tips.
No display
Check for 24 VAC at thermostat; display
is blank when 24 VAC is not present.
System fan does not
Verify that wiring is correct.
come on properly
All thermostat buttons
Verify that 24 VAC is present; unit
are inoperative
locks out when 24 VAC is not present.
Thermostat turns on and
Adjust temperature differential (see
off too frequently
Setting a New Temperature Differential).
Program schedule activates
Check time (AM/PM) set on
at the wrong time
thermostat (see
Programming
).
Thermostat does not
Verify that it is in
Program
mode;
PROG
follow program
displays solid; check time (AM/PM);
check if in
Hold
mode (
PROG
flashing).
“PROG” flashes
Press
Hold
button to remove from
(in Hold mode)
Hold
mode.
Fan runs continuously
Check
Fan Auto/On
switch. If set to
ON
position, fan will run continuously.
Room temperature is
Verify that wall hole is plugged
not correct
with putty or insulation.
Compressor doesn’t run
There is a 3 minute time delay and a
or turn off immediately
3 minute minimum run time for the
when changing function
compressor when it turns on/off.
or setting
Fan doesn’t run or turn off
This is normal. On some models, the
immediately when changing
fan may have a 3 minute minimum
function or setting
run time/off time delay.
“LO bat” displays on screen
Replace batteries with 2 fresh “AA”
alkaline batteries.
Display reads “12:00 PM”
Set clock/time.
Problem not listed above
Press the
Reset
button once. Reset
button function: time, day and mode
changed to last saved settings (saved
after power loss or when exiting
program setup; configuration and
program settings are unchanged).
Problem
Solution
20
