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SERVICING
High Voltage!
Disconnect all power before servicing or
installing. Multiple power sources may be present.
Failure to do so may cause property damage,
personal injury or death.
1. Disassemble and remove the heating element(s).
2. Visually inspect the heater assembly for any breaks
in the wire or broken insulators.
3. Using an ohmmeter, test the element for continuity -
no reading indicates the element is open. Replace as
necessary.
Refrigeration Repair Practice
Always remove the refrigerant charge in a proper manner
before applying heat to the system.
These models use the FasTest Access Fitting System,
with a saddle that is either soldered to the suction and
liquid lines or is fastened with a locking nut to the access
fitting box (core) and then screwed into the saddle. Do not
remove the core from the saddle until the refrigerant
charge has been removed. Failure to do so could result
in property damage or personal injury.
When installing a new core or reinstalling the core after
removal, it is very important to note that before inserting
the core into the saddle, the core and saddle must be
free of debris and the "O" Ring must have a thin coating
of refrigerant oil applied to it. The oil is to prevent the "O"
Ring from being deformed when the core is tightened
completely. The core should be torqued to 8 ft. lb.
When repairing the refrigeration system:
1. Never open a system that is under vacuum. Air and
moisture will be drawn in.
2. Plug or cap all openings.
3. Remove all burrs and clean the brazing surfaces of
the tubing with sand cloth or paper. Brazing materials
do not flow well on oxidized or oily surfaces.
4. Clean the inside of all new tubing to remove oils and
pipe chips.
5. When brazing, sweep the tubing with dry nitrogen
to prevent the formation of oxides on the inside
surfaces.
6. Complete any repair by replacing the liquid line drier
in the system, evacuate and charge.
At any time the system has been open for repair, the
factory installed liquid line filter drier must be replaced.
WARNING
DANGER
Brazing Materials
Copper to Copper Joints - Sil-Fos used without flux
(alloy of 15% silver, 80% copper, and 5% phosphorous).
Recommended heat 1400°F.
Copper to Steel Joints - Silver Solder used without
a flux (alloy of 30% silver, 38% copper, 32% zinc).
Recommended heat - 1200°F.
Standing Pressure Test (Recommended Before
System Evacuation)
To avoid the risk of fire or explosion, never use oxygen,
high pressure air or flammable gases for leak testing of a
refrigeration system.
To avoid possible explosion, the line from the nitrogen
cylinder must include a pressure regulator and a pressure
relief valve. The pressure relief valve must be set to open at
no more than 450 PSIG.
Using dry nitrogen, pressurize the system to 450 PSIG.
Allow the pressure to stabilize and hold for 15 minutes
(minimum). If the pressure does not drop below 450 PSIG,
the system is considered leak free. Proceed to system
evacuation using the Deep Vacuum Method. If after 15
minutes the pressure drops below 450 PSIG, follow the
procedure outlined below to identify system leaks. Repeat
the Standing Pressure Test.
Leak Testing (nitrogen or nitrogen-traced)
To avoid the risk of fire or explosion, never use oxygen,
high pressure air or flammable gases for leak testing of a
refrigeration system.
To avoid possible explosion, the line from the nitrogen
cylinder must include a pressure regulator and a pressure
relief valve. The pressure relief valve must be set to open at
no more than 450 PSIG.
Leak test the system using dry nitrogen and soapy
water to identify leaks. If you prefer to use an electronic
leak detector, charge the system to 10 PSIG with the
appropriate system refrigerant (See Serial Data Plate
for refrigerant identification). Using dry nitrogen, finish
charging the system to 450 PSIG. Apply the leak detector
to all suspect areas. When leaks are discovered, repair
the leaks, and repeat the pressure test. If leaks have been
eliminated proceed to system evacuation.
WARNING
WARNING
WARNING
WARNING
22
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