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121
DIAGNOSTIC ALARM CODES AND POSSIBLE CAUSES
T048 (Ckt A, Oil Return Not Reliable with Only One Comp
Available)
T049 (Ckt B, Oil Return Not Reliable with Only One Comp
Available)
Alert codes T048 and T049 are for circuits A and B respective-
ly and are active for size 090 and 100 units only. Size 090 and
100 units have 3 compressors per circuit. If load conditions are
such that only one compressor is running on a circuit, a second
compressor is periodically turned on to equalize compressor oil
levels. If a second compressor is unavailable for oil return, the
circuit will be shut down, and an alert will be generated. The
alert will automatically clear, and the circuit will restart when a
second compressor becomes available.
T051 (Circuit A, Compressor 1 Failure)
T052 (Circuit A, Compressor 2 Failure)
T053 (Circuit A, Compressor 3 Failure)
T054 (Circuit B, Compressor 1 Failure)
T055 (Circuit B, Compressor 2 Failure)
T056 (Circuit B, Compressor 3 Failure)
If the current sensor board reads OFF while the compressor re-
lay has been commanded ON for a period of 4 continuous sec-
onds, an alert is generated.
Any time this alert occurs, a strike will be logged on the affect-
ed compressor. If three successive strikes occur, the compres-
sor will be locked out requiring a manual reset or power reset
of the unit.
The clearing of strikes during compressor operation is a combi-
nation of 3 complete cycles or 15 continuous minutes of run
time operation. So, if there are one or two strikes on the com-
pressor and three short cycles (ON-OFF, ON-OFF, ON-OFF)
occur in less than 15 minutes, the strikes will be reset to zero
for the affected compressor. Also, if the compressor turns on
and runs for 15 minutes straight with no compressor failure,
the compressor's strikes are cleared as well.
NOTE: Until the compressor is locked out, for the first two strikes,
the alert will not be broadcast to the network, nor will the alarm re-
lay be closed.
The possible causes are:
• High pressure switch open. The high pressure switch for
each circuit is wired in series with the compressor
contactor coils of each compressor on the circuit to disable
compressor operation immediately upon a high discharge
pressure condition. If the high pressure switch opens while
the MBB or CXB is commanding the compressor ON, the
compressor stops and the CSB no longer detects current,
causing the control to activate the alert.
• Compressor circuit breaker tripped.
• Failed CSB or wiring error.
To check out alerts T051, T052, T053, T054, T055, T056:
1. Turn on faulty compressor using Service Test mode. If the
compressor does not start, then most likely the problem is
one of the following: HPS is open, compressor circuit
breaker is tripped, incorrect control wiring, or incorrect
compressor wiring.
2. If the compressor starts, verify that the indoor and outdoor
fans are operating properly.
A620
Economizer 2 Actuator Out of Calibration
Alarm only
Automatic
A621
Economizer 2 Actuator Comm Failure
No IGV functions
Automatic
T622
Economizer 2 Actuator Control Range Increased
Alert only
Automatic
A623
Econ2 Overload, Setpt Not Reached
Alarm only
Automatic
A624
Econ2 Actuator Hunting Excessively
Alert only
Automatic
T625
Econ 2 (Return) Not Economizing When It Should
Alert only
Automatic
T626
Econ 2 (Return) Economizing When It Should Not
Alert only
Automatic
T627
Econ 2 (Return) Damper Stuck Or Jammed
Alert only
Automatic
T630
Humidifier Actuator Out of Calibration
Alert only
Automatic
T631
Humidifier Actuator Communication Failure
No humidifier functions
Automatic
T632
Humidifier Actuator Control Range Increased
Alert only
Automatic
T633
Humidifier Act Overload, Setpt Not Reached
Alert only
Automatic
T634
Humidifier Actuator Hunting Excessively
Alert only
Automatic
A640
Heating Coil Actuator Out of Calibration
Alarm only
Automatic
A641
Heating Coil Actuator Comm Fail
No heating coil functions
Automatic
T642
Heat Coil Actuator Control Range Increased
Alert only
Automatic
A643
Ht Coil Act Ovrload, Setpt Pos Not Reached
Alarm only
Automatic
A644
Heat Coil Actuator Hunting Excessively
alarm only
Automatic
A650
Bldg.Press. Actuator 1 Out of Calibration
Alarm only
Automatic
A651
Bldg.Press. Actuator 1 Comm Failure
No building pressure control
Automatic
T652
Bldg.Press. Act. 1 Control Range Increased
Alert only
Automatic
A653
BP Act. 1 Overload, Setpnt Pos Not Reached
Alarm only
Automatic
A654
Bldg.Press. Actuator 1 Hunting Excessively
Alert only
Automatic
A660
Bldg.Press. Actuator 2 Out of Calibration
Alarm only
Automatic
A661
Bldg.Press. Actuator 2 Comm Failure
No building pressure control
Automatic
T662
Bldg.Press. Act. 2 Control Range Increased
Alert only
Automatic
A663
BP Act. 2 Overload, Setpnt Pos Not Reached
Alarm only
Automatic
A664
BP Actuator 2 Hunting Excessively
Alert only
Automatic
A700
Air Temp Lvg Supply Fan Thermistor Failure
Unit shut down
Automatic
T701
Staged Heat 1 Thermistor Failure
Average remaining sensors
Automatic
T702
Staged Heat 2 Thermistor Failure
Average remaining sensors
Automatic
T703
Staged Heat 3 Thermistor Failure
Average remaining sensors
Automatic
A704
Staged Heat Lvg Air Temp Sum Total Failure
No staged heat function
Automatic
T705
Limit Switch Thermistor Failure
No software limit switch function
Automatic
A706
Hydronic Evap Discharge Thermistor Failure
Unit shut down
Automatic
T707
Digital Scroll Discharge Temperature Failure
Digital compressor A1 limited to 50% Automatic
Table 104 — Alert and Alarm Codes (cont)
ALARM OR
ALERT
NUMBER
DESCRIPTION
ACTION TAKEN BY CONTROL
RESET METHOD
Summary of Contents for Weathermaster 48P2030-100
Page 130: ...130 Fig 19 Typical Power Schematic Sizes 040 075 Shown ...
Page 131: ...131 Fig 20 Main Base Board Input Output Connections ...
Page 132: ...132 Fig 21 RXB EXB CEM SCB Input Output Connections ...
Page 133: ...133 Fig 22 Typical Gas Heat Unit Control Wiring 48P030 100 Units Shown ...
Page 134: ...134 Fig 23 Typical Electric Heat Wiring 50P030 100 Units Shown ...
Page 135: ...135 Fig 24 Typical Power Wiring 115 V ...
Page 136: ...136 Fig 25 Typical Gas Heat Section Size 030 050 Units Shown ...
Page 138: ...138 Fig 27 Component Arrangement Size 030 035 Units ...
Page 139: ...139 Fig 28 Component Arrangement Size 040 075 Units ...
Page 140: ...140 Fig 29 Component Arrangement Size 090 100 Units ...