25
PTEC-M-1A
Refrigeration
System
Dehydrating and Evacuating
Refrigeration System
A rather popular misconception
exists that since air conditioners
normally operate with a refrigerant
temperature above 32°F, moisture in
the system is harmless. Nothing
could be further from the truth.
Oxygen from moisture in addition to
normal compressor and motor heat
reacts chemically with the refrigerant
and oil to form corrosive
hydrochloric and hydrofluoric acids.
These acids contribute to the break
down of motor winding insulation
and the corrosion of compressor
working parts and cause
unnecessary compressor failure.
Sludge, which is a residue of the
chemical action, coats all
compressor parts, the inside of
refrigerant tubing, and may even
restrict refrigerant flow through the
capillary tube(s).
Leak Testing
Refrigerant leaks are best detected
with a halide or electronic leak
detector.
The importance of careful leak
testing cannot be over emphasized.
Undetected leaks invariably lead to
repeated calls and eventually result
in system contamination, restrictions
and burned out compressors.
For a system that contains a
refrigerant charge and is suspected
of having a leak, stop the operation,
check all tubing and fittings. Soap
suds may also be used.
Note:
The flame of the halide
detector will glow green in the
presence of R22 refrigerant.
If a leak is detected, do not attempt
to apply more brazing material to the
joint. Recover the charge, unbraze
the joint, clean and rebraze.
For a system that has been newly
repaired and does not contain a
charge, connect a cylinder of
refrigerant, through a gauge
manifold, to the process tube of the
compressor and liquid line strainer.
Open the valve on the cylinder and
manifold and allow the pressure to
build up within the system. Check for
and handle leaks as described
above.
After the test has been completed,
recover the test charge, evacuate the
system, and recharge with clean
refrigerant.
Brazing
Important Note: Brazing requires high
temperatures. Take precaution to
protect against personal injury or
property damage.
Satisfactory results require
cleanliness, experience and the use
of proper material and equipment.
The connections to be brazed must
be properly sized, free of rough
edges and clean.
The generally accepted materials
are:
SIL-FOS
(Alloy of 15% silver, 80%
copper, 5% phosphorus) is used
without flux on copper to copper.
DO
NOT USE FOR A COPPER TO
STEEL
CONNECTION. Recommended heat
is approximately 1400°F.
SILVER SOLDER
(Alloy of 30% silver,
38% copper, 32% zinc) is used with
fluoride base flux on copper to steel,
brass to copper, steel to steel, brass
to steel. Recommended heat is
approximately 1200°F.
Содержание PTEC-070
Страница 22: ...PTEC M 1A 22 Refrigeration System PTEC Refrigeration System...
Страница 54: ...PTEC M 1A 54 Schematic Diagrams PTEC and PTHC Condensate Pump One Stage Heat...
Страница 55: ...55 PTEC M 1A Schematic Diagrams PTEC and PTHC Condensate Pump Two Stage Heat...
Страница 56: ...PTEC M 1A 56 Schematic Diagrams PTEC and PTHC Power Vent One Stage Heat...
Страница 57: ...57 PTEC M 1A Schematic Diagrams PTEC and PTHC Power Vent Two Stage Heat...
Страница 58: ...PTEC M 1A 58 PTEC and PTHC Power Door One Stage Heat Schematic Diagrams...
Страница 59: ...59 PTEC M 1A Schematic Diagrams PTEC and PTHC Power Door Two Stage Heat...
Страница 60: ...PTEC M 1A 60 Schematic Diagrams PTEC and PTHC Condensate Pump with Power Vent One Stage Heat...
Страница 61: ...61 PTEC M 1A Schematic Diagrams PTEC and PTHC Condensate Pump with Power Vent Two Stage Heat...
Страница 62: ...PTEC M 1A 62 Schematic Diagrams Hydronic...
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