Amana AB2026PEK, GB1924PEK, AB2526PEK, G32026PEK, G32526PEK Instruction Manual
...
Service
This manual is to be used by qualified appliance
technicians only. Maytag does not assume any
responsibility for property damage or personal
injury for improper service procedures done by
an unqualified person.
International
Bottom Mount
Refrigerators
This Base Manual covers general information
Refer to individual Technical Sheet
for information on specific models
This manual includes, but is
not limited to the following:
Amana
AB1924PEK*
AB2026PEK*
AB2225PEK*
AB2226PEK*
AB2526PEK*
G32026PEK*
G32526PEK*
GB1924PEK*
GB2225PEK*
GB2526PEK*
16023324
July 2004
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!
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Important Information
Important Notices for Servicers and Consumers
Maytag will not be responsible for personal injury or property damage from improper service procedures. Pride and
workmanship go into every product to provide our customers with quality products. It is possible, however, that
during its lifetime a product may require service. Products should be serviced only by a qualified service technician
who is familiar with the safety procedures required in the repair and who is equipped with the proper tools, parts,
testing instruments and the appropriate service information. IT IS THE TECHNICIANS RESPONSIBILITY TO
REVIEW ALL APPROPRIATE SERVICE INFORMATION BEFORE BEGINNING REPAIRS.
WARNING
To avoid risk of severe personal injury or death, disconnect power before working/servicing on appliance to avoid
electrical shock.
To locate an authorized servicer, please consult your telephone book or the dealer from whom you purchased this
product. For further assistance, please contact:
Customer Service Support Center
CAIR Center
Web Site Telephone Number
WWW.AMANA.COM ............................................... 1-800-843-0304
WWW.JENNAIR.COM ............................................ 1-800-536-6247
WWW.MAYTAG.COM ............................................. 1-800-688-9900
CAIR Center in Canada .......................................... 1-800-688-2002
Amana Canada Product .......................................... 1-866-587-2002
Recognize Safety Symbols, Words, and Labels
DANGER
DANGER—Immediate hazards which WILL result in severe personal injury or death.
WARNING
WARNING—Hazards or unsafe practices which COULD result in severe personal injury or death.
CAUTION
CAUTION—Hazards or unsafe practices which COULD result in minor personal injury, product or property
damage.
2 16023324 Rev. 0 ©2004 Maytag Services
Table of Contents
Important Information .................................................... 2
Product Design ............................................................. 4
Component Testing ....................................................... 5
Service Procedures ......................................................10
Service Equipment .......................................................10
Drier Replacement ....................................................... 10
Refrigerant Precautions ................................................ 11
Line Piercing Valves ..................................................... 11
Open Lines .................................................................. 11
Compressor Operational Test ....................................... 11
Dehydrating Sealed Refrigeration System .................... 12
Leak Testing .................................................................12
Testing Systems Containing a
Refrigerant Charge ................................................. 12
Testing Systems Containing
No Refrigerant Charge ............................................12
Restrictions .................................................................. 13
Symptoms .............................................................13
Testing for Restrictions .......................................... 13
Evacuation and Charging .............................................. 14
Evacuation .............................................................14
Charging ................................................................ 15
Refrigerant Charge ................................................. 15
HFC134a Service Information ....................................... 16
Health, Safety, and Handling ..................................16
Comparison of CFC12 and HFC134a Properties .....16
Replacement Service Compressor ................................17
Compressor Testing Procedures ............................ 17
Brazing ........................................................................ 17
Refrigerant Flow ...........................................................18
Cabinet Air Flow ...........................................................19
Two Way Machine Compartment Air Flow Diagram ...... 20
One Way Machine Compartment
Air Flow Diagram .........................................................21
Typical External Sweat Pattern...................................22
Troubleshooting Chart................................................23
System Diagnosis ........................................................26
Disassembly Procedures
Fresh Food Door ....................................................29
Freezer Door ..........................................................29
Freezer Drawer ......................................................29
Refrigerator Compartment
Light Bulb ..............................................................29
Light Bulb Assembly .............................................. 29
Light Bulb Sockets ................................................ 30
PC Control Board ...................................................30
Light Switch ...........................................................30
Temp- Assure™ Damper control ............................30
Fresh Food Thermistor ...........................................30
Water Tank ............................................................30
Water Dispenser ....................................................31
Freezer Compartment
Freezer Thermistor ................................................. 31
Light Socket .......................................................... 31
Light Switch ...........................................................31
Freezer Back Panel ............................................... 31
Evaporator Fan and Evaporator Motor ................... 31
Defrost Terminator (thermostat) ..............................32
Defrost Heater ....................................................... 32
Evaporator Removal ...............................................32
Drawer Assembly ................................................... 33
Drawer Rails ..........................................................33
Rack and Pinion Gear ............................................ 33
Bottom of Cabinet
Front roller assembly ............................................. 33
Rear roller assembly............................................33
Machine Compartment
Condenser Fan and Fan motor ............................... 33
Compressor ........................................................... 33
Overload/Relay/Capacitor ....................................... 34
Condensate Drain Pan ........................................... 34
Condensate Drain Tube ..........................................34
Condenser Removal ............................................... 34
Control Board ( Mid Level)
Programming Mode ............................................... 35
Defrost Operation ...................................................35
Forced Defrost Mode ............................................. 35
Service Test Mode .................................................36
Service Test 1-Defrost Thermostat & Defrost Circuit
Test ....................................................................... 37
Service Test 2-Compressor/Condenser Fan Test ....37
Service Test 3-Evaporator/Freezer Fan Test ........... 37
Service Test 4-Fresh Food Thermistor Test ............ 38
Service Test 5-Freezer Thermistor Test .................. 38
Service Test 6-Open Damper Test ..........................39
Service Test 7-FF Performance Adjustment ............ 39
Service Test 8-FZ Performance Adjustment ............39
©2004 Maytag Services 16023324 Rev. 0 3
Product Design
!
WARNING
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 earthing wires are connected before certifying unit as repaired and/or operational.
Refrigeration System
Compressor forces high temperature vapor into fan
cooled tube and wire condenser where vapor is cooled
and condensed into high pressure liquid by circulation
of air across condenser coil. (See Refrigerant Flow
Diagram, page 18)
High pressure liquid passes into post-condenser loop
which helps to prevent condensation around freezer
compartment opening and through molecular sieve drier
and into capillary tube. Small inside diameter of
capillary offers resistance, decreasing pressure, and
temperature of liquid discharged into evaporator.
Capillary diameter and length is carefully sized for each
system.
Capillary enters evaporator at top front. Combined liquid
and saturated gas flows through front to bottom of coil
and into suction line. Aluminum tube evaporator coil is
located in freezer compartment where circulating
evaporator fan moves air through coil and into fresh food
compartment.
Large surface of evaporator allows heat to be absorbed
from both fresh food and freezer compartments by
airflow over evaporator coil causing some of the liquid to
evaporate. Temperature of evaporator tubing near end of
running cycle may vary from -25°C to -32°C.
Saturated gas is drawn off through suction line where
superheated gas enters compressor. To raise
temperature of gas, suction line is placed in heat
exchange with capillary.
Defrost System
Mid Level Electronic Defrost
The Control Board adapts the compressor run time
between defrosts to achieve optimum defrost intervals
by monitoring the length of time the defrost heater is
on.
After initial power up, defrost interval is 4 hours
compressor run time. Defrost occurs immediately after
the 4 hours.
Note: Once unit is ready to defrost there is a 4 minute
wait time prior to the beginning of the defrost
cycle.
Optimum defrost is 15 minutes. Each additional minute
the defrost thermostat remains closed, 1 hr. is
subtracted from the previous defrost interval. Each
minute the thermostat opens prior to optimum defrost,
it extends the next defrost interval 1 hr. When defrost
thermostat opens there is a 4-6 minute drip time before
compressor restarts or Control Board will terminate
defrost at 25 minutes if defrost thermostat has not
opened and will reset the defrost interval to the 8 hr.
minimum setting.
4 hours of continuous compressor run resets the next
defrost interval to 8 hours and will initiate a defrost, if 8
hours of compressor run time has also occurred.
Temperature Controls
Freezer compartment temperature is regulated by air
sensing thermostat at top front of freezer compartment
which actuates compressor. Control should be set to
maintain freezer temperature between -17.8°C to -
18.9°C.
Fresh food compartment temperature is regulated by an
air damper control governing amount of refrigerated air
entering fresh food compartment from freezer. Fresh
food compartment temperature should be between
3.3°C and 4.4°C.
4 16023324 Rev. 0 ©2004 Maytag Services
Component Testing
!
WARNING
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 earthing wires are connected before certifying unit as repaired and/or operational.
Component Description Test Procedures
Compressor
When compressor electrical circuit is
energized, the start winding current
causes relay to heat. After an amount of
starting time, the start winding circuit
turns off. The relay will switch off the start
winding circuit even though compressor
has not started (for example, when
attempting to restart after momentary
power interruption).
With “open” relay, compressor will not
start because there is little or no current
to start windings. Overload protection will
open due to high locked rotor run winding
current.
With “shorted” relay or capacitor,
compressor will start and overload
protector will quickly open due to high
current of combined run and start
windings.
With open or weak capacitor, compressor
will start and run as normal but will
consume more energy.
Resistance test
1. Disconnect power to unit.
2. Discharge capacitor by shorting across terminals with a resistor for 1 minute.
NOTE: (Some compressors do not have a run capacitor.)
3. Remove leads from compressor terminals.
4. Set ohmmeter to lowest scale.
5. Check for resistance between
Terminals “S” and “C”, start winding
Terminals “R” and “C”, run winding
If either compressor winding reads open (infinite or very high resistance) or
dead short (0 ohms), replace compressor.
Ground test
1. Disconnect power to refrigerator.
2. Discharge capacitor, if present, by shorting terminals through a resistor.
3. Remove compressor leads and use an ohmmeter set on highest scale.
4. Touch one lead to compressor body (clean point of contact) and other probe
to each compressor terminal.
• If reading is obtained, compressor is grounded and must be replaced.
Operation test
If voltage, capacitor, overload, and motor winding tests do not show cause for
failure, perform the following test:
1. Disconnect power to refrigerator.
2. Discharge capacitor by shorting capacitor terminals through a resistor.
3. Remove leads from compressor terminals.
4. Wire a test cord to power switch.
5. Place time delayed fuse with UL rating equal to amp rating of motor in test
cord socket. (Refer to Technical Data Sheet)
6. Remove overload and relay.
7. Connect start, common and run leads of test cord on appropriate terminals of
compressor.
8. Attach capacitor leads of test cord together. If capacitor is used, attach
capacitor lead to a known good capacitor of same capacity.
To AC supply
©2004 Maytag Services
Switch
Compressor
Fuses
CRS
Capacitor
Test configuration
9. Plug test cord into multimeter to determine start and run wattage and to check
for low voltage, which can also be a source of trouble indications.
10. With power to multimeter, press start cord switch and release.
• If compressor motor starts and draws normal wattage, compressor is okay
and trouble is in capacitor, relay/overload, freezer temperature control, or
elsewhere in system.
• If compressor does not start when direct wired, recover refrigerant at high
side. After refrigerant is recovered, repeat compressor direct wire test. If
compressor runs after recovery but would not run when direct wired before
recover, a restriction in sealed system is indicated.
• If compressor does not run when wired direct after recovery, replace faulty
compressor.
16023324 Rev. 0 5
Component Testing
!
WARNING
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 earthing wires are connected before certifying unit as repaired and/or operational.
Component Description Test Procedures
Capacitor
Condenser Condenser is a tube and wire
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.
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, as gas temperature is
reduced, 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. 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 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 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 condenser the refrigerant flows into
a post condenser loop which helps
control exterior condensation on flange,
center mullion, and around freezer door.
Refrigerant the flows through the drier to
evaporator and into compressor through
suction line.
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. Remove capacitor cover and disconnect capacitor wires.
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. 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 16.20 Bar 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.
WARNING
!
WARNING
!
6 16023324 Rev. 0
©2004 Maytag Services
Component Testing
!
WARNING
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 earthing wires are connected before certifying unit as repaired and/or operational.
Component Description Test Procedures
Overload / Relay
Control board
Ice maker Optional on some models.
Evaporator fan
motor
Electric damper
control
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
terminal 3. L2 side of 120 VAC power is
connected to relay terminal 2.
On some models.
See “Control Board” section for
troubleshooting information.
See “Ice Maker” section for service
information.
Evaporator fan moves air across
evaporator coil and throughout refrigerator
cabinet.
Damper control balances the air delivery
between refrigerator and freezer
compartments providing temperature
control for refrigerator.
Electrical voltage activates damper control
and door closes restricting flow of air from
freezer compartment to refrigerator
compartment.
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
1. Disconnect power to unit.
2. Disconnect fan motor leads.
3. Check resistance from ground connection solder. Trace to motor frame must
not exceed .05 ohms.
4. Check for voltage at connector to motor with unit in refrigeration mode and
compressor operating.
Check resistance across terminals.
If no resistance across terminals replace damper control.
©2004 Maytag Services
16023324 Rev. 0 7
Component Testing
!
WARNING
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 earthing wires are connected before certifying unit as repaired and/or operational.
Component Description Test Procedures
Switch, refrigerator
light,
Switch, freezer
light
Switch, water
dispenser
Drier
Single pole, single throw switch
completes circuit for light when door is
open.
Single pole, double throw switch
completes circuit for light when door is
open. Opens circuit to icemaker when
door is open.
Single pole, single throw switch
completes circuit for water solenoid when
button is depressed.
Drier is placed at post condenser loop
outlet and passes liquefied refrigerant to
capillary.
Desiccant (20) 8 x 12 4AXH - 7 M>S> Grams
Check resistant across terminals.
Switch arm depressed
“NO” terminals Open
Switch arm up
“NO” terminals Closed
Check resistant across terminals.
Switch arm depressed
“NO” terminals Open
”NC” terminals Closed
Switch arm up
“NO” terminals Closed
“NC” terminals Open
Check resistant across terminals.
Water button not depressed
“NO” terminals Open
Water button depressed
“NO” terminals Closed
Drier must be changed every time the system is opened for testing or
compressor replacement.
NOTE: Drier used in R12 sealed system is not interchangeable with
drier used in R134a sealed system. Always replace drier in R134a
system with Amana part number B2150504.
Before opening refrigeration system, recover HFC134a refrigerant for safe
disposal.
1. Cut drier out of system using the following procedure. Do not unbraze drier.
2. Applying heat to remove drier will drive moisture into the system.
3. Score capillary tube close to drier and break.
4. Reform inlet tube to drier allowing enough space for large tube cutter.
5. Cut circumference of drier 31.75 mm below condenser inlet tube joint to drier.
6. Remove drier.
7. Apply heat trap paste on post condenser tubes to protect grommets from high
heat.
8. Unbraze remaining part of drier. Remove drier from system.
9. Discard drier in safe place. Do not leave drier with customer. If refrigerator is
under warranty, old drier must accompany warranty claim.
To avoid death or severe personal injury, cut drier at correct location.
Cutting drier at incorrect location will allow desiccant beads to scatter. If
spilled, completely clean area of beads.
WARNING
!
8 16023324 Rev. 0
©2004 Maytag Services
Component Testing
!
WARNING
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 earthing wires are connected before certifying unit as repaired and/or operational.
Component Description Test Procedures
Evaporator Inner volume of evaporator allows liquid
Evaporator heater
(defrost)
Thermostat
(defrost)
Thermistor
Condenser motor
ECM condenser
motor
refrigerant discharged from capillary to
expand into refrigerant gas.
Expansion cools evaporator tube and fin
temperature to approximately -20°F
transferring heat from freezer section to
refrigerant.
Passing through suction line to
compressor, the refrigerant picks up
superheat (a relationship between
pressure and temperature that assures
complete vaporization of liquid
refrigerant) as the result of capillary tube
soldered to suction line.
Refrigerant gas is pulled through suction
line by compressor, completing
refrigeration cycle.
Activated when defrost thermostat,
defrost timer, and freezer control
complete circuit through heater.
Thermostat is in a series circuit with
terminal 2 of defrost timer, and defrost
heater. Circuit is complete if evaporator
fan motor operates when cold.
Controls the circuit from freezer
thermostat through defrost terminator to
defrost heater. Opens and breaks circuit
when thermostat senses preset high
temperature.
Temperature sensing device Check resistance across leads.
Condenser fan moves cooling air across
condenser coil and compressor body.
Condenser fan motor is in parallel circuit
with compressor.
Condenser fan moves cooling air across
condenser coil and compressor body.
Condenser fan motor is in parallel circuit
with compressor.
Test for leaks in evaporator with electronic leak detector or with soap solution.
Compressor oil is circulated with refrigerant; check for oil when checking for
leaks.
For minute leaks:
1. Separate evaporator from rest of refrigeration system and pressurize
evaporator up to a maximum of 9.65 Bar 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.
Check resistance across heater.
To check defrost system:
1. Thermocouple defrost thermostat and plug refrigerator into wattmeter.
2. Turn into defrost mode. Wattmeter should read specified watts (according to
Technical Data Sheet).
3. When defrost thermostat reaches specified temperature ±15°C (see
Technical Data Sheet), thermostat should interrupt power to heater.
Test continuity across terminals.
With power off and evaporator coil below freezing, thermostat should show
continuity when checked with ohmmeter. See “Heater, evaporator (defrost)”
section for additional tests.
After defrost thermostat opens, thermostat remains open until end of defrost cycle
and refrigerator starts cooling again. Defrost thermostat senses a preset low
temperature and resets (closes).
Temperature Resistance
25°C 10,000 ohms
2.2°C 29,500 ohms
-17.7°C 86,300 ohms
Check resistance across coil.
Check resistance across coil.
©2004 Maytag Services
16023324 Rev. 0 9
Service Procedures
!
WARNING
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 earthing wires are connected before certifying unit as repaired and/or operational.
Service Equipment
Listed below is equipment needed for proper servicing
of HFC134a systems. Verify equipment is confirmed
by manufacturer as being compatible with HFC134a
and ester oil system.
Equipment must be exclusively used for HFC134a.
Exclusive use of equipment only applies to italic items.
• Evacuation pump
Check with vacuum pump supplier to verify equipment
is compatible for HFC134a. Robinair, Model 15600
2 stage, 6 cubic feet per minute pump is
recommended.
• Four-way manifold gauge set, with low loss hoses
• Leak detector
•
Charging cylinder
• Line piercing saddle valve
(Schroeder valves). Seals must be HFC134a and
ester oil compatible. Line piercing valves may be used
for diagnosis but are not suitable for evacuation or
charging, due to minute holes pierced in tubing. Do
not leave mechanical access valves on system.
Valves eventually will leak. Molecules of HFC134a are
smaller than other refrigerants and will leak where
other refrigerants would not.
• Swagging tools
•
Flaring tools
• Tubing cutter
• Flux
• Sil-Fos
• Silver solder
• Oil for swagging and flaring
Use only part # R0157532
• Copper tubing
Use only part # R0174075 and # R0174076
• Dry nitrogen
99.5% minimum purity, with -40°C or lower dew point
• Crimp tool
• Tube bender
• Micron vacuum gauge
• Process tube adaptor kit
• Heat trap paste
• ICI appliance grade HFC134a
Drier Replacement
Before opening refrigeration system, recover
HFC134a refrigerant for safe disposal.
Every time sealed HFC134a system is repaired, drier
filter must be replaced with, part # B2150504.
Cut drier out of system by completing the following
steps. Do not unbraze drier filter. Applying heat to
remove drier will drive moisture into system.
WARNING
!
To avoid risk of severe personal injury or death, cut
drier at correct location. Cutting drier at incorrect
location will allow desiccant beads to scatter.
Completely clean area of beads, if spilled.
1. Score capillary tube close to drier and break.
2. Reform inlet tube to drier allowing enough space
for large tube cutter.
3. Cut circumference of drier at 31.75 millimeters,
below condenser inlet tube joint to drier.
4. Remove drier.
5. Apply heat trap paste on post condenser tubes to
protect grommets from high heat.
6. Unbraze remaining part of drier. Remove drier
from system.
7. Discard drier in safe place. Do not leave drier with
customer. If refrigerator is under warranty, old
drier must accompany warranty claim.
10 16023324 Rev. 0 ©2004 Maytag Services
Service Procedures
!
WARNING
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 earthing wires are connected before certifying unit as repaired and/or operational.
Refrigerant Precautions
WARNING
!
To avoid risk of personal injury, do not allow
refrigerant to contact eyes or skin.
CAUTION
!
To avoid risk of property damage, do not use
refrigerant other than that shown on unit serial
number identification plate.
NOTE: All precautionary measures recommended by
refrigerant manufacturers and suppliers apply
and should be observed.
Line Piercing Valves
Line piercing valves can be used for diagnosis, but
are not suitable for evacuating or charging due to
holes pierced in tubing by valves.
NOTE: Do not leave line piercing valves on system.
Connection between valve and tubing is not
hermetically sealed. Leaks will occur.
Open Lines
During any processing of refrigeration system, never
leave lines open to atmosphere. Open lines allow water
vapor to enter system, making proper evacuation more
difficult.
Compressor Operational Test
(short term testing only)
If compressor voltage, capacitor, overload, and motor
winding tests are successful (do not indicate a fault),
perform the following test:
1.Disconnect power to unit.
2.Discharge capacitor by shorting capacitor
terminals through a resistor.
NOTE: Not all units have run capacitor.
3.Remove leads from compressor terminals.
4.Attach test cord to compressor windings.
• Common lead on test cord attaches to C terminal
on compressor.
• Start lead on test cord attaches to S terminal on
compressor.
• Run lead on test cord attaches to M terminal on
compressor.
To AC supply
Switch
Compressor
Fuses
Attaching Capacitor for Compressor Test
5. Connect a known good capacitor into circuit as shown
above. For proper capacitor size and rating, see
technical data sheet for unit under test.
NOTE: Ensure test cord cables and fuses meet
specifications for unit under test (see Technical
Sheet for unit under test).
6. Replace compressor protector cover securely.
7. Plug test cord into outlet, then press and release start
cord switch.
CAUTION
!
To avoid risk of damage to compressor windings,
immediately disconnect (unplug) test cord from power
source if compressor does not start. Damage to
compressor windings occurs if windings remain
energized when compressor is not running.
If compressor runs when direct wired, it is working
properly. Malfunction is elsewhere in system.
If compressor does not start when direct wired, recover
system at high side. After the system is recovered,
repeat compressor direct wire test.
If compressor runs after system is recovered (but
would not operate when wired direct before recovery) a
restriction in sealed system is indicated.
If motor does not run when wired direct after recovery,
replace faulty compressor.
CRS
Capacitor
©2004 Maytag Services 16023324 Rev. 0 11
Service Procedures
!
WARNING
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 earthing wires are connected before certifying unit as repaired and/or operational.
Dehydrating Sealed Refrigeration System
Moisture in a refrigerator sealed system exposed to
heat generated by the compressor and motor reacts
chemically with refrigerant and oil in the system and
forms corrosive hydrochloric and hydrofluoric acids.
These acids contribute to breakdown of motor winding
insulation and corrosion of compressor working parts,
causing compressor failure.
In addition, sludge, a residue of the chemical reaction,
coats all surfaces of sealed system, and will eventually
restrict refrigerant flow through capillary tube.
To dehydrate sealed system, evacuate system (see
paragraph
Evacuation
).
Leak Testing
DANGER
!
To avoid risk of serious injury or death from violent
explosions, NEVER use oxygen or acetylene for
pressure testing or clean out of refrigeration
systems. Free oxygen will explode on contact with
oil. Acetylene will explode spontaneously when put
under pressure.
Testing Systems Containing No Refrigerant Charge
1. Connect cylinder of nitrogen, through gauge
manifold, to process tube of compressor and liquid
line strainer.
2. Open valves on nitrogen cylinder and gauge manifold.
Allow pressure to build within sealed system.
3. Check for leaks using soap suds.
If a leak is detected in a joint, do not to attempt to repair
by applying additional brazing material. Joint must be
disassembled, cleaned and rebrazed. Capture refrigerant
charge (if system is charged), unbraze joint, clean all
parts, then rebraze.
If leak is detected in tubing, replace tubing. If leak is
detected in either coil, replace faulty coil.
It is important to check sealed system for refrigerant
leaks. Undetected leaks can lead to repeated service
calls and eventually result in system contamination,
restrictions, and premature compressor failure.
Refrigerant leaks are best detected with halide or
electronic leak detectors.
Testing Systems Containing a Refrigerant Charge
1. Stop unit operation (turn refrigerator off).
2. Holding leak detector exploring tube as close to
system tubing as possible, check all piping, joints,
and fittings.
NOTE: Use soap suds on areas leak detector cannot
reach or reliably test.
12 16023324 Rev. 0 ©2004 Maytag Services
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