80 Series Thermostats
54
Troubleshooting Continued
Symptom
Possible Cause
Corrective Action
Thermostat Display &
Thermometer Disagree
Thermostat display requires adjustment.
Display can be ad/-5 degrees. See User Menu item 05.
Furnace (Air Conditioner)
Cycles Too Fast or Slow
(narrow or wide
temperature swing)
The location of the thermostat and/ or the size of the
Heating System may be influencing the cycle rate
Digital thermostats provide precise control and cycle faster than
older mechanical models. The system turns on and off more
frequently, but runs for a shorter time. If you would like to increase
cycle time, choose SLO for slow cycle in the Installer menu.
(Reference menu items 30, 32, & 35). If an acceptable cycle rate is
not achieved, contact your HVAC service person. Cycle rate is
dependent on system sizing. Undersized or oversized systems may
cycle faster or slower than optimal and require additional heating or
cooling capacity or duct balancing to achieve an optimal cycle rate
for comfort.
“Call for Service” icon
appears on display
1.) Heating system is not able to heat the space to within
10 degrees of the setpoint within 2 hours.
2.) Cooling system is not able to cool the space to within
10 degrees of the setpoint within 2 hours
3.) If “—” is displayed for the Room Temperature, a
replacement thermostat is needed.
4.) None of the buttons operate on the thermostat.
5.) If “Call for Service” is flashing, compressor self
diagnostic is detecting an issue with the outdoor unit.
1.) See corrective action for “No Heat”.
2.) See corrective action for “No Cool”.
3.) Replace thermostat.
4.) Make sure keypad lockout is not turned on.
5.) Contact a service person to verify the outdoor equipment is
operating correctly.
Resetting the Thermostat or Thermostat Settings
If the thermostat has good batteries, but has a blank display or does not respond to key presses, the thermostat
should be reset by removing the batteries for 2 minutes. This reset will not change the menu settings or program. If
the condition persists after reinstalling the batteries, replace the thermostat.
To conveniently reset only the schedule and user settings back to factory defaults, press
MENU
and
BACKLIGHT
buttons at the same time and hold until the display goes blank and resets.
Summary of Contents for 80 Series
Page 1: ...80 Series Thermostats 1 Emerson 80 Series Thermostats ...
Page 2: ...Business and Product Overview ...
Page 19: ...Technical ...
Page 32: ...Install ...
Page 35: ...80 Series Thermostats 35 Instruction Sheets 1F85U 42PR 1F85U 42NP 1F85U 22PR 1F85U 22NP ...
Page 44: ...80 Series Thermostats 44 Installer Configuration Menu ...