Honeywell RTH9580 Wi-Fi, User Manual, Page: 73 / 160

71
If you have difficulty with your thermostat, please try the following suggestions. Most
problems can be corrected quickly and easily.
Display is
blank
• 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 11)
.
Cannot change
system setting
to Cool
• Check that System Setup screen “Your thermostat controls” or “Your
system type” is set to match your heating and cooling equipment (see
page 65).
Fan does
not turn on
when heat is
required
• Check that System Setup screen “Your fan control” is set to match your
heating equipment (see page 66).
“Wait” appears
on the screen
• Compressor protection feature is engaged. Wait 5 minutes for the system
to restart safely, without damage to the compressor.
Troubleshooting