R-410A SEALED REFRIGERATION SYSTEM REPAIRS
IMPORTANT
SEALED SYSTEM REPAIRS TO
EQUIPMENT REQUIRED:
1.Voltmeter
2.Ammeter
3.Ohmmeter
4.E.P.A. Approved Refrigerant Recovery System
5.Vacuum Pump (capable of 200 microns or less vacuum.)
6.Acetylene Welder
7.Electronic Halogen Leak Detector capable of
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8.Accurate refrigerant charge measuring device such as:
a.Balance Scales - 1/2 oz. accuracy
b.Charging Board - 1/2 oz. accuracy
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10.Low Pressure Gauge -
11.Vacuum Gauge - (0 - 1000 microns)
)DFLOLWLHVIRUÀRZLQJQLWURJHQWKURXJKUHIULJHUDWLRQWXELQJ during all brazing processes.
EQUIPMENT MUST BE CAPABLE OF:
1.Recovering refrigerant to EPA required levels.
2.Evacuation from both the high side and low side of the system simultaneously.
3.Introducing refrigerant charge into high side of the system.
4.Accurately weighing the refrigerant charge introduced into the system.
WARNING
RISK OF ELECTRIC SHOCK
Unplug and/or disconnect all electrical power to the unit before performing inspections, maintenances or service.
Failure to do so could result in electric shock, VHULRXVLQMXU\RUGHDWK
WARNING
HIGH PRESSURE HAZARD
Sealed Refrigeration System contains refrigerant and oil under high pressure.
Proper safety procedures must be followed, and proper protective clothing must be worn when working with refrigerants.
Failure to follow these procedures could UHVXOWLQVHULRXVLQMXU\RUGHDWK
Proper refrigerant charge is essential to proper unit operation. Operating a unit with an improper refrigerant charge will UHVXOWLQUHGXFHGSHUIRUPDQFH FDSDFLW\ DQGRUHI¿FLHQF\ Accordingly, the use of proper charging methods during servicing will insure that the unit is functioning as designed and that its compressor will not be damaged.
7RRPXFKUHIULJHUDQW RYHUFKDUJH LQWKHV\VWHPLVMXVWDVEDG (if not worse) than not enough refrigerant (undercharge). They both can be the source of certain compressor failures if they remain uncorrected for any period of time. Quite often, other SUREOHPV VXFK DV ORZ DLU ÀRZ DFURVV HYDSRUDWRU HWF DUH misdiagnosed as refrigerant charge problems. The refrigerant circuit diagnosis chart will assist you in properly diagnosing these systems.
An overcharged unit will at times return liquid refrigerant (slugging) back to the suction side of the compressor eventually causing a mechanical failure within the compressor. This mechanical failure can manifest itself as valve failure, bearing IDLOXUH DQGRU RWKHU PHFKDQLFDO IDLOXUH 7KH VSHFL¿F W\SH RI IDLOXUHZLOOEHLQÀXHQFHGE\WKHDPRXQWRIOLTXLGEHLQJUHWXUQHG and the length of time the slugging continues.
Refrigerant Charging
NOTE: Because the Kuhl Q system is a sealed system, service process tubes will have to be installed. First install a line tap and remove refrigerant from system. Make necessary sealed system repairs and vacuum system. Crimp process tube line and solder end shut. Do not leave a service valve in the sealed system.
Not enough refrigerant (undercharge) on the other hand, will cause the temperature of the suction gas to increase to WKHSRLQWZKHUHLWGRHVQRWSURYLGHVXI¿FLHQWFRROLQJIRUWKH compressor motor. When this occurs, the motor winding temperature will increase causing the motor to overheat and possibly cycle open the compressor overload protector. Continued overheating of the motor windings and/or cycling of the overload will eventually lead to compressor motor or overload failure.
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