Problem: Honeywell wall thermostat (7 years old) was turning central A/C on and off perfectly as recently as 1 hour ago. However, suddenly the following is happening:
Switches set to COOL and AUTO, nothing happens (no A/C, no fan) even though temp is set to 60 and room temp is 80.
Switches set to OFF and FAN ON, the fan comes on.
Switches set to COOL and FAN ON, fan comes on but no A/C.
Any thoughts why the COOL/AUTO combo suddenly doesn't work?