898150-UIM-B-0113
26
Johnson Controls Unitary Products
E4
Discharge line
temperature protection
Sensor RT5 monitors compressor dis-
charge line temperature and communi-
cates with outdoor unit microprocessor.
Depending on the temperature measured,
the compressor speed will be increased to
meet the load or will continue to run at the
existing speed. If the temperature
becomes excessively high, the compres-
sor will be de-energized. When the com-
pressor discharge temperature drops
below 194ºF (90ºC), the unit will resume
normal operation.
• Check for low refrigerant charge.
• Check for restricted refrigerant flow due
to blocked capillary.
E5
Compressor over-current protection
All system functions are terminated except
indoor fan.
• Check for locked compressor rotor due to
excessively high ambient temperature.
• Check for restricted refrigerant flow due
to blocked capillary tubing.
• Check outdoor unit to make sure that coil
is not blocked.
E6
Communication failure between
indoor unit and outdoor unit
All system functions are terminated except
indoor fan.
• Check indoor to outdoor field wiring to
confirm (N) 1 from indoor goes to (N) 1
outdoor, terminal 2 from indoor goes to ter-
minal 2 outdoors and terminal 3 indoors
goes to terminal 3 in outdoor.
• Communications between indoor and
outdoor unit may have been cut due to the
installation of a condensate pump and
connected as illustrated in figure 46.
E7 Mode
conflict
If the outdoor unit for example is operating
in heating mode based on demand from a
indoor unit and there is a call for cooling at
one of the other indoor zone unit. The
indoor unit will display E7.
Normal system operation.
E8
Compressor high
temperature protection
All system functions are terminated after
three-minute delay except indoor fan.
Refer to the ProficienTECH Ductless Splits
Technical Training Manual.
FA
Over tube temperature
drop frequency
Elevated temperature sensors readings
will adjust compressor frequency. Specific
temperature sensor values will reduce
compressor frequency.
• Check for locked compressor rotor due to
excessively high ambient temperature.
• Check for restricted refrigerant flow due
to blocked capillary tubing.
• Check outdoor unit to make sure that coil
is not blocked.
FC
Door malfunction
Access door malfunction
Only floor standing units. Unit will cycled
OFF.
FE
Compressor overload
sensor malfunction
Compressor overload sensor issue (Open
contacts). Unit will cycled OFF.
• Check for locked compressor rotor due to
excessively high ambient temperature.
• Check for restricted refrigerant flow due
to blocked capillary tubing.
• Check outdoor unit to make sure that coil
is not blocked.
FH
Anti-freezing upper
and lower limit range
Compressor will run at reduced speed until
temperature increases.
Wait for temperature to increase above
42.8ºF (6ºC), then recheck operation sta-
tus.
F0
Indoor coil is gathering refrigerant
All system functions are terminated except
indoor fan.
Pump refrigerant into outdoor unit. Check
2-way shut-off valve in small line to see if it
is closed or if flow is restricted. Correct, if
necessary.
F1
Indoor ambient sensor (RT1)
open or short circuited
Cooling and dehumidification modes will
continue to operate as well as indoor fan.
Unit will not operate in heating mode.
• Check sensor to ensure that it is in
acceptable range.
• Check sensor for proper resistance.
• Replace sensor if shorted, open or
out-of-calibration.
TABLE 12:
Error Codes
Indoor Character
Display
System Status
Troubleshooting for
Possible Causes
