Method Of Charging / Repairs
The acceptable method for charging the RAC system is the Weighed in Charge Method. The weighed in charge method is applicable to all units. It is the preferred method to use, as it is the most accurate.
The weighed in method should always be used whenever a charge is removed from a unit such as for a leak repair, compressor replacement, or when there is no refrigerant charge left in the unit. To charge by this method, requires the following steps:
1.Install a piercing valve to remove refrigerant from the sealedsystem. (Piercing valve must be removed from the system before recharging.)
2.Recover Refrigerant in accordance with EPA regulations.
WARNING
BURN HAZARD
Proper safety procedures must be followed, and proper protective clothing must be worn when working with a torch.
Failure to follow these procedures could result in moderate or serious injury.
3. Install a process tube to sealed system.
CAUTION
FREEZE HAZARD
Proper safety procedures must be followed, and proper protective clothing must be worn when working with liquid refrigerant.
Failure to follow these procedures could result in minor to moderate injury.
4.Make necessary repairs to system.
5.Evacuate system to 200 microns or less.
6.Weigh in refrigerant with the property quantity of
7.Start unit, and verify performance.
WARNING
BURN HAZARD
Proper safety procedures must be followed, and proper protective clothing must be worn when working with a torch.
Failure to follow these procedures could result in moderate or serious injury.
8. Crimp the process tube and solder the end shut.
WARNING
ELECTRIC SHOCK HAZARD
Turn off electric power before service or installation.
Extreme care must be used, if it becomes necessary to work on equipment with power applied.
Failure to do so could result in serious injury or death.
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 result in serious injury or death.
Undercharged Refrigerant Systems
An undercharged system will result in poor performance (low pressures, etc.) in both the heating and cooling cycle.
Whenever you service a unit with an undercharge of refrigerant, always suspect a leak. The leak must be repaired before charging the unit.
To check for an undercharged system, turn the unit on, allow the compressor to run long enough to establish working pressures in the system (15 to 20 minutes).
During the cooling cycle you can listen carefully at the exit of the metering device into the evaporator; an intermittent hissing and gurgling sound indicates a low refrigerant charge. Intermittent frosting and thawing of the evaporator is another indication of a low charge, however, frosting and thawing can also be caused by insuffi cient air over the evaporator.
Checks for an undercharged system can be made at the compressor. If the compressor seems quieter than normal, it is an indication of a low refrigerant charge.
A check of the amperage drawn by the compressor motor should show a lower reading. (Check the Unit Specifi cation.)
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