Friedrich V(E Manuale Utente

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Method Of Charging
The acceptable method for charging the Vert-I-Pak 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 
sealed system.  (Piercing valve must be removed from 
the system before recharging.)
2.  Recover Refrigerant in accordance with EPA 
regulations.
3.  Install a process tube to sealed system.
4.  Make necessary repairs to system.
5.  Evacuate system to 300 microns or less.
6.  Weigh in refrigerant with the property quantity of 
R-22 refrigerant.
7.  Start unit, and verify performance.
8.  Crimp the process tube and solder the end shut.
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 under charge 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, 
NOTE:  In order to access the sealed system it will be necessary to install Schrader type 
fi ttings to the process tubes on the discharge and suction of the compressor. Proper 
recovery refrigerant procedures need to be adhered to as outlined in EPA Regulations.  
THIS SHOULD ONLY BE ATTEMPTED BY QUALIFIED SERVICE PERSONNEL.
Undercharged Refrigerant Systems
it is an indication of a low refrigerant charge. A check of the 
amper age drawn by the compressor motor should show a 
lower reading. (Check the Unit Specifi cation.)  After the unit 
has run 10 to 15 minutes, check the gauge pressures.
Gauges connected to system with an under charge will 
have low head pressures and substantially low suction 
pressures.