Reciprocating compressors are the most common
found for older air conditioning and heating systems.
Reciprocating hermetic compressors do not require a
shaft seal. The drive motor is completely inside the
compressor shell. External terminals are air and
moisture tight. There is a major difference between the
sealed hermetic and the bolted, or semi -hermitic
compressor. The hermetic is in a two-section housing of
stamped or formed sheet steel, instead of cast iron.
After the motor and compressor are assembled, the
housing or shell sections are welded together.
The sealed reciprocating compressor
has three basic advantages over the open type
compressor. It requires no shaft seal. It is more
compact. It cost less than either the open type
compressor or the semi-hermetic compressor. There are
some disadvantages, too. If either the motor or the
compressor malfunction, the entire compressor must be
replaced. The motor as actually a part of the
refrigeration circulation system. This means that
burnout can contaminate the entire system. In most
sealed hermetic compressors, the motor has the advantage
for being cooled by the refrigerant vapor from the
suction line. The vapor flows over the motor windings
after entry into the housing of the compressor.
Hermetic compressors may be
installed in hermetically sealed systems. These systems
no access for service to the gas compression portion of
the system. These systems are normally small systems and
are sealed at the factory. This allows the system to
operate trouble free for many years with out loss of
refrigerant or contamination of the system.
A reciprocating compressor is a
positive-displacement compressor that can have one or
more cylinders in various configurations. All
reciprocating compressors have the same basic parts.
There is a piston with the sealing rings for each
piston. A crankshaft has a connecting rod for each
piston. discharge and suction valves (usually reed or
ring type) are assembled on valve plates. These are
separated by a dividing wall in a removable cylinder
head for each cylinder. (While the welded cylinder head
may be removed by removing the bolts, hermetic
compressors cannot be serviced without first cutting
apart the compressor shell. This is usually considered
impractical).
Reciprocating hermetic
compressors is what Las Vegas Air Conditioning Repair
does best. Las Vegas Air Conditioning Repair shows how a
reciprocating hermetically sealed compressor works. Most
commonly found on older air conditioning systems.
Hermetically Sealed Reciprocating Compressors
Capacities
Hermitically sealed
reciprocating compressors come in sizes ranging
fractional up to about 20 tons. They are non-serviceable
units. They are found in household and commercial
refrigeration, air conditioning and heat pump
applications. |
