103
Table 84 — Cooling Service Analysis
LEGEND
PROBLEM CAUSE
REMEDY
Compressor and Fan Will Not
Start.
Power failure.
Call power company.
Fuse blown or circuit breaker tripped. Check CB1,
CB2, and CB3.
Replace fuse or reset circuit breaker.
Disconnect off.
Power disconnect.
Compressor time guard to prevent short cycling.
Check using
Comfort
Link
scrolling marquee.
Thermostat or occupancy schedule set point not call-
ing for Cooling.
Check using
Comfort
Link
scrolling marquee.
Outdoor temperature too low.
Check Compressor Lockout Temperature (MC.LO)
using
Comfort
Link
scrolling marquee.
Active alarm.
Check active alarms using
Comfort
Link
scrolling
marquee.
Compressor Cycles (Other Than
Normally Satisfying Thermostat).
Insufficient line voltage.
Determine cause and correct.
Active alarm.
Check active alarms using
Comfort
Link
s
crolling
marquee.
Compressors Operates
Continuously.
Unit undersized for load.
Decrease load or increase of size of unit.
Thermostat or occupancy schedule set point too low.
Reset thermostat or schedule set point.
Dirty air filters.
Replace filters.
Low refrigerant charge.
Check pressure, locate leak, repair evacuate, and
recharge.
Condenser coil dirty or restricted.
Clean coil or remove restriction.
Excessive Head Pressures.
Loose condenser thermistors.
Tighten thermistors.
Dirty condenser coil.
Clean coil.
Refrigerant overcharge.
Recover excess refrigerant.
Faulty TXV.
1. Check TXV bulb mounting and secure tightly to
suction line and insulate.
2. Replace TXV (and filter drier) if stuck open or
closed.
Condenser air restricted or air short cycling.
Determine cause and correct.
Restriction in liquid tube.
Remove restriction.
Condenser Fans Not Operating.
No Power to contactors.
Fuse blown or plug at motor loose.
Excessive Suction Pressure.
High heat load.
Check for sources and eliminate
Faulty TXV.
1. Check TXV bulb mounting and secure tightly to
suction line and insulate.
2. Replace TXV (and filter drier) if stuck open or
closed.
Refrigerant overcharged.
Recover excess refrigerant.
Suction Pressure Too Low.
Dirty air filters.
Replace air filters.
Low refrigerant charge.
Check for leaks, repair, and recharge.
Faulty TXV.
1. Check TXV bulb mounting and secure tightly to
suction line and insulate.
2. Replace TXV (and filter drier) if stuck open or
closed.
Insufficient evaporator airflow.
Check belt tension. Check for other restrictions.
Temperature too low in conditioned area (low return-air
temperature).
Reset thermostat or occupancy schedule.
CB
—
Circuit Breaker
TXV —
Thermostatic Expansion Valve
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 ...