Tecumseh AH5540E - Starting a System with Liquid Refrigerant in the Compressor

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SERVICE HANDBOOK
Starting a System with Liquid Refrigerant in the Compressor
When most air conditioning and commercial systems are started up for the first time each season,
a large part of the system refrigerant charge is in the compressor. If there is no crankcase heater
or the heat is not operating properly and the unit must be started at the time of the service, then
follow these guidelines:
• DO NOT attempt to heat the crankcase by applying a flame to the compressor. Not
only is this process slow and likely to be ineffective, it may damage electrical wires,
paint, and the oil.
• If there is no evidence of a compressor electrical problem (for example, tripped breaker
or blown fuse or reports of such), then “jog” the compressor. To “jog” the compressor,
apply power for one to two seconds, then wait 1 to 2 minutes. After 3 or 4 jogs, apply
power continuously.
WARNING! Jogging a compressor that has an electrical problem can increase the
likelihoodofterminalventing.Toreducetheriskofseriousburnsordeathfromterminal
ventingwithignition,youmust FIRST checkforagroundfaultwheneveryou suspect an
electricalproblem.See“IdentifyingCompressorElectricalProblems”onpages40-41for
additionalinformation.
FIGURE 6-8: Wiring diagram for PSC compressor with run capacitance off-cycle heat.
Internal
Thermal Protector
(optional)
External
Thermal Protector
Motor
Star t Winding
Main Winding
Bleeder
Resistor
Run Capacitor
Single Can
(Split Capacitor Optional)
Bleeder
Resistor
Single Pole Contactor
or On - O Switch
Temperature Control
(Room Air Conditioner)
Single Phase - PSC Type
Single Phase - CSR Type
Potential Rela y
Line 1
Rela y - Potential
Line 2
Ground
Start
Capacitor
A B
C
R
L
2
T
2
5
2
1
Hi
Side
Fan
S
C
L
1
Compressor -
Unit
Ground