Component Testing
28
©2007 Viking Preferred Service
Component Description
Test
Procedures
Condenser
Condenser is a tube and wire
construction located in machine
compartment.
Condenser is on high pressure
discharge side of compressor.
Condenser function is to transfer
heat absorbed by refrigerant to
ambient.
Higher pressure gas is routed to
condenser where gas condenses
into a high pressure liquid state.
Heat transfer takes place
because discharged gas is at a
higher temperature than air that
is passing over condenser.
Adequate air flow over condenser
must be maintained.
Condenser is air cooled by
condenser fan motor. If efficiency
of heat transfer from condenser
to surrounding air is impaired,
condensing temperature
becomes higher. High liquid
temperature means liquid will not
remove as much heat during
boiling in evaporator as under
normal conditions. This would be
indicated by higher than normal
head pressures, long run time,
and high wattage. Remove any
obstruction that would restrict
normal air movement through
condenser.
From condenser the refrigerant
flows into a post condenser loop
which helps control exterior
condensation on flange, center
mullion, and around freezer door.
Refrigerant then flows through
the drier to evaporator and into
compressor through suction line
Leaks in condenser can usually be detected by using an
electronic leak detector or soap solution. Look for signs of
compressor oil when checking for leaks. A certain amount
of compressor oil is circulated with refrigerant.
Leaks in post condenser loop are rare because loop is a
one-piece copper tube.
For minute leaks
1. Separate condenser from rest of refrigeration system
and pressurize condenser up to a maximum of 235 PSI
with a refrigerant and dry nitrogen combination.
2. Recheck for leaks.
WARNING
To avoid severe personal injury or death from
sudden eruption of high pressures gases, observe
the following:
Protect against a sudden eruption if high pressures
are required for leak checking. Do not use high
pressure compressed gases in refrigeration systems
without a reliable pressure regulator and pressure
relief valve in the lines.
Overload/Relay When voltage is connected and
relay is cool, current passes
through relay to start winding.
After a short time, current heats
the resistor in relay and
resistance will rise blocking
current flow through relay.
Start winding remains in the
circuit through run capacitor.
Solid state relay plugs directly on
compressor start and run
terminals. Relay terminals 2 and
3 are connected within relay. Run
capacitor is connected to relay.
1. Disconnect power to the refrigerator.
2. Remove relay cover and disconnect leads.
3. Check resistance across terminals 2 and 3 with an
ohmmeter:
•
Normal = 3 to 12 ohms
•
Shorted = 0 ohms
•
Open = infinite ohms
