Diagnostic Label - York R-410A Installation Manual

66901 / 035-20393-001 Rev. C (1204)
TM
Comfort Alert Diagnostics — The Comfort Alert
module facilitates troubleshooting heat pump and air conditioning sys-
tem failures. This Comfort Alert
phase systems with scroll compressors that have internal overload pro-
tection. By monitoring and analyzing data from the compressor and the
thermostat demand, the module can detect the cause of electrical and
system related failures without any sensors. A flashing LED indicator
communicates the ALERT code and guides the service technician more
quickly and accurately to the root cause of a problem.
NOTE: This module does not provide safety protection! The Comfort
TM
Alert module is a monitoring device and cannot control or shut down
other devices.
LED Description (See Table 1)
POWER LED (Green): indicates voltage is present at the power con-
nection of the module. ALERT LED (Yellow): communicates an abnor-
mal system condition through a unique flash code. The ALERT LED will
flash a number of times consecutively, pause and then repeat the pro-
cess. The number of consecutive flashes, defined as the Flash Code,
correlates to a particular abnormal condition. Detailed descriptions of
specific ALERT Flash Codes are shown in Table 6 of this manual.
TABLE 6: Diagnostic Label
Status LED Status LED Description
Green "POWER" Module has power
Thermostat demand signal Y1 is present,
Red "TRIP"
but the compressor is not running
Yellow "ALERT" System Pressure Trip
Flash Code 2 Low pressure switch fault
Yellow "ALERT" Short Cycling
Flash Code 3 Compressor is running only briefly
Yellow "ALERT"
Locked Rotor
Flash Code 4
Yellow "ALERT"
Open Circuit
Flash Code 5
Yellow "ALERT" Open Start Circuit
Flash Code 6 Current only in run circuit
Yellow "ALERT" Open Run Circuit
Flash Code 7 Current only in start circuit
Yellow "ALERT" Welded Contactor
Flash Code 8 Compressor always runs
Yellow "ALERT" Low Voltage
Flash Code 9 Control circuit < 17 VAC
10
TM
diagnostics
TM
module is designed only for single-
TRIP LED (Red): indicates there is a demand signal from the thermo-
stat but no current to the compressor is detected by the module. The
TRIP LED typically indicates the compressor protector is open or may
indicate missing supply power to the compressor.
The scroll compressor's run (R), common (C) and start (S) wires are
routed through the holes in the Comfort Alert
and "S."
24 VAC Power Wiring — The Comfort Alert
stant nominal 24 VAC power supply. The wiring to the module's R and C
terminals must be directly from the indoor unit or thermostat.
TM
The Comfort Alert module requires a thermostat demand signal to
operate properly.
NOTE: After the thermostat demand signal is connected, verify that 24
when demand is present
VAC across Y and C
Status LED Troubleshooting Information
Supply voltage is present at module terminals
1. Compressor protector is open
2. Outdoor unit power disconnect is open
3. Compressor circuit breaker or fuse(s) is open
4. Broken wire or connector is not making contact
5. Low pressure switch is open
6. Compressor contactor has failed open
1. Low refrigerant charge
2. Evaportor blower is not running
3. Evaportor coil is frozen
4. Faulty metering device
5. Condenser coil is dirty
6. Liquid line restriction (filter drier blocked if present in system)
1. High pressure switch fault
2. Condenser coil poor air circulation (dirty, blocked, damaged)
3. Condenser fan is not running
4. Return air duct has substantial leakage
5. Thermstat demand signal is intermittent
1. Run capacitor has failed
2. Low line voltage (contact utility if voltage at disconnect is low)
3. Excessive liquid refrigerant in compressor
4. Compressor bearings are seized
1. Outdoor unit power disconnect is open
2. Compressor circuit breaker or fuse(s) is open
3. Compressor contactor has failed open
4. Low pressure switch is open
5. Open circuit in compressor supply wiring or connections
6. Unusually long compressor protector reset time due to exteme ambient
termperature
7. Compressor windings are damaged
1. Run capacitor has failed
2. Open circuit in compressor start wiring or connections
3. Compressor start winding is damaged
1. Open circuit in compressor run wiring or connections
2. Compressor run winding is damaged
1. Compressor contactor has failed closed
2. Thermostat demand signal not connected to module
1. Control circuit transformer is overloaded
2. Low line voltage (contact utility if voltage at disconnect is low)
TM
module marked "R," "C"
TM
module requires a con-
.
Unitary Products Group