Capacitor; Condenser - Maytag ATB1821AR series Service Manual

Component Testing
To avoid risk of electrical shock, personal injury, or death, disconnect electrical power source to unit, unless test
procedures require power to be connected. Discharge capacitor through a resistor before attempting to service.
Ensure all ground wires are connected before certifying unit as repaired and/or operational.
Component Description

Capacitor

Run capacitor connects to relay terminal
3 and L side of line.
Some compressors do not require a run
capacitor; refer to the Technical Data
Sheet for the unit being serviced.

Condenser

Condenser is a long folded tube
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 circulated through
condenser where, as gas temperature is
reduced, It 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. It is very
important that adequate air flow over
condenser is maintained.
Condenser is air cooled by condenser fan
motor. If efficiency of heat transfer from
condenser to surrounding air is impaired,
condensing temperature will increase.
High liquid temperature means liquid will
not remove as much heat during boiling
in evaporator as under normal conditions.
This would be indicated by high than
normal head pressures, long run time,
and high wattage. Remove any lint or
other accumulation, that would restrict
normal air movement through condenser.
From the condenser the refrigerant flows
into a post condenser loop which helps
control exterior condensation on flange,
center mullion, and around freezer door.
Refrigerant flows through the drier to the
capillary tube to the evaporator and back
to the compressor through suction line.
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WARNING
Test Procedures
To avoid electrical shock which can cause severe personal injury or death,
discharge capacitor through a resistor before handling.
1. Disconnect power to refrigerator.
2. Disconnect the capacitor wires if present.
3. Discharge capacitor by shorting across terminals with a resistor for 1 minute.
4. Check resistance across capacitor terminals with ohmmeter set on "X1K"
scale.
• Good—needle swings to 0 ohms and slowly moves back to infinity.
• Open—needle does not move. Replace capacitor.
• Shorted—needle moves to zero and stays. Replace capacitor.
• High resistance leak—needle jumps toward 0 and then moves back to
constant high resistance (not infinity).
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 that
may indicate the location of the leak. A certain amount of compressor oil is
circulated with refrigerant.
Leaks in post condenser loop are rare because loop is a one-piece steel tube.
"For small 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.
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.
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WARNING
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WARNING
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