User Guide

ECT MODBUS The RS485 Network and Hardware Setup • 6-9
Comfort Alert Codes
The thermostat supports the Emerson Climate Tech-
nologies Comfort Alert system. On any alert present on
Comfort Alert terminal, the thermostat keeps the informa-
tion on the fault available over the network so that the E2
can access this information. On some specific alerts, it will
discontinue compressor operation if active protection is
enabled.
The Comfort Alert codes are sent separately from the diag-
nostic codes. Just like the diagnostic codes, the Comfort
Alert codes are entered as advisories in the E2 advisory
log.
Cool Eight Hours If cool runs for over 8 hours continuously, the thermostat sets anticipator to
zero until call for cool is satisfied.
Cooling Problem Detected
Fan Not Detected If the fan is activated and if the Fan Detect input is enabled, the thermostat
checks its status 15 seconds after the fan is energized, and if the fan is not
on, it disables any active heat or cool calls, and report an alarm.
Proof Fail
Frost Protection Activated The thermostat allows a frost protection menu option. When enabled, frost
protection is enabled in all system modes including OFF, when temperature
drops below 42°F (5.5 °C).All other heat / cool calls are disabled, and
indoor heat is activated until the temperature rises above the frost protec-
tion threshold.
Frost Protection
Diagnostic Alarm Descriptions E2 Advisory
Table 6-5
-Diagnostic Alarm Outputs
Comfort Alert Descriptions Cause E2 Advisory
Long Run Time Compressor is running extremely
long run cycles (typically for
more than 18 hours).
• Low refrigerant charge.
• Evaporator blower is not running.
• Evaporator coil is frozen.
• Faulty metering device
• Condenser coil is dirty
• Thermostat is malfunctioning
• Compressor Second Stage Cooling Wiring
Compressor run time is long
System Pressure
Trip
Discharge or pressure out of lim-
its or compressor overloaded.
• High head pressure.
• Condenser coil poor air circulation (dirty,
blocked, damaged)
• Condenser fan is not running
• Return air duct has substantial leakage.
System pressure trip
Short Cycling Compressor is running only
briefly.
• Thermostat demand signal is intermittent.
• Time delay relay or control board is defec-
tive.
• If high pressure switch present, check if there
is a System Pressure Trip problem.
Compressor short cycling
Locked Rotor Locked rotor. • Run capacitor has failed.
• Low line voltage (contact utility if voltage at
disconnect is low).
• Excessive liquid refrigerant in compressor.
• Compressor bearings have seized.
Locked Rotor Trip
Table 6-6 -Comfort Alert Outputs