Troubleshooting - Honeywell RTH8500 Series User Manual

Troubleshooting

If you have difficulty with your thermostat, please try the following suggestions.
Most problems can be corrected quickly and easily.
Display is
blank
Cannot change
system setting
to Cool
Fan does
not turn on
when heat is
required
"Wait" appears
on the screen
Heat pump
issues cool air
in heat mode,
or warm air in
cool mode
Button on
lower right of
screen is blank
Red light is on
Heating or
cooling system
does not
respond
Heating system
is running in
cool mode
33-00133ES—01
• Check circuit breaker and reset if necessary.
• Make sure power switch at heating and cooling system is on.
• Make sure furnace door is closed securely.
• Make sure C wire is connected (see page 6).
• Check Function 0170: System Type to make sure it is set to match your
heating and cooling equipment (see page 22).
• Check Function 0180: Heating Fan Control to make sure it is set to match
your heating equipment (see page 22).
• Compressor protection feature is engaged. Wait 5 minutes for the system to
restart safely, without damage to the compressor.
• Check Function 0190: Heat Pump Changeover Valve to make sure it is
properly configured for your system (see page 22).
• This button will remain blank unless the furnace filter change reminder is
activated (see page 17).
• If thermostat is in Emergency Heat mode the red light is normal. It shows
that the thermostat is in emergency heat mode.
• If thermostat is not in Emergency Heat mode, contact a qualified service
contractor for repair.
• Press to set system to Heat. Make sure the temperature is set
SYSTEM
higher than the Inside temperature.
• Press to set system to Cool. Make sure the temperature is set lower
SYSTEM
than the Inside temperature.
• Check circuit breaker and reset if necessary.
• Make sure power switch at heating & cooling system is on.
• Make sure furnace door is closed securely.
• If "Wait" is displayed, the compressor protection timer is on. Wait 5 minutes
for the system to restart safely, without damaging the compressor (see page
19).
• Check Function 0170: System Type to make sure it is set to match your
heating and cooling equipment (see page 22).
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