GVZC20 Service Manual
IMPORTANT INFORMATION
2
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 qualied service technician who
is familiar with the safety procedures required in the repair
and who is equipped with the proper tools, parts, testing in-
struments and the appropriate service manual.
OUTSIDE THE U.S., .
(Not a technical assistance line for dealers.) Your telephone company will bill you for the call.
HIGH VOLTAGE !
D
ISCONNECT ALL POWER BEFORE SERVICING.
M
ULTIPLE POWER SOURCES MAY
BE PRESENT. FAILURE
TO DO SO MAY CAUSE PROPERTY DAMAGE, PERSONAL
INJURY OR DEATH.
D
O
NOT
CONNECT
TO
OR
USE
ANY
DEVICE
THAT
IS
NOT
DESIGN
CERTIFIED
BY
THE
MANUFACTURER
FOR
USE
WITH
THIS
UNIT
. S
ERIOUS
PROPERTY
DAMAGE
,
PERSONAL
INJURY
,
REDUCED
UNIT
PERFORMANCE
AND
/
OR
HAZARDOUS
CONDITIONS
MAY
RESULT
FROM
THE
USE
OF
SUCH
NON
-
APPROVED
DEVICES
.
While these items will not cover every conceivable situa-
tion, they should serve as a useful guide.
REFRIGERANTS ARE HEAVIER THAN AIR. THEY CAN “PUSH OUT” THE
OXYGEN IN
YOUR LUNGS
OR IN ANY ENCLOSED SPACE. T
O AVOID
POSSIBLE DIFFICULTY
IN BREATHING OR DEATH:
• N
EVER
PURGE REFRIGERANT
INTO
AN ENCLOSED
ROOM
OR SPACE. B
Y
LAW
, ALL
REFRIGERANTS MUST BE RECLAIMED.
• I
F AN INDOOR LEAK IS SUSPECTED, THOROUGHLY
VENTILATE THE AREA
BEFORE BEGINNING
WORK.
• L
IQUID
REFRIGERANT CAN
BE VERY
COLD. TO AVOID POSSIBLE
FROST BITE
OR BLINDNESS, AVOID CONTACT AND WEAR GLOVES AND GOGGLES. IF
LIQUID
REFRIGERANT DOES CONTACT YOUR SKIN OR EYES, SEEK
MEDICAL
HELP IMMEDIATELY.
• A
LWAYS FOLLOW EPA REGULATIONS. NEVER BURN REFRIGERANT, AS
P
OISONOUS GAS WILL BE PRODUCED.
THE UNITED STATES ENVIRONMENTAL PROTECTION AGENCY (”EPA”)
HAS ISSUED VARIOUS REGULATIONS
REGARDING THE INTRODUCTION
AND DISPOSAL OF REFRIGERANTS INTRODUCED INTO THIS UNIT.
FAILURE TO FOLLOW THESE REGULATIONS MAY HARM THE
ENVIRONMENT AND CAN LEAD TO THE IMPOSITION OF SUBSTANTIAL
FINES. THESE REGULATIONS MAY VARY BY JURISDICTION. SHOULD
QUESTIONS ARISE, CONTACT YOUR LOCAL EPA OFFICE.
T
O
AVOID POSSIBLE EXPLOSION:
•NEVER
APPLY
FLAME OR STEAM TO A REFRIGERANT
CYLINDER. IF
YOU
MUST HEAT A CYLINDER FOR
FASTER CHARGING, PARTIALLY IMMERSE
IT IN WARM WATER.
•NEVER FILL
A CYLINDER
MORE THAN 80% FULL
OF LIQUID
REFRIGERANT.
•NEVER ADD ANYTHING OTHER THAN R-410A TO A RETURNABLE
R-410A CYLINDER. THE
SERVICE EQUIPMENT USED
MUST BE LISTED
OR CERTIFIED
FOR THE TYPE OF REFRIGERANT USE
.
•STORE CYLINDERS IN
A COOL, DRY
PLACE. NEVER USE A CYLINDER
AS A
PLATFORM OR A ROLLER.
CHECKING COMPRESSOR EFFICIENCY .............. 23
THERMOSTATIC EXPANSION VALVE ..................... 23
OVERFEEDING ........................................................... 23
UNDERFEEDING ........................................................ 23
SUPREHEAT ............................................................... 23
CECKING SUBCOOLING ........................................... 24
CHECKING THERMOSTATIC EXPANSION VALVE
OPERATION ................................................................ 25
NON-CONDENSABLES .............................................. 25
COMPRESSOR BURNOUT ....................................... 25
REFRIGERANT PIPING ............................................. 26
DUCT STATIC PRESSURES AND/OR STATIC PRES-
SURE DROP ACROSS COILS ................................... 30
AIR HANDLER EXTERNAL STATIC .......................... 30
COIL STATIC PRESSURE DROP .............................. 30
INDOOR UNIT TROUBLESHOOTING ...................... 32
HEAT PUMP ADVANCE FEATURE MENU ............... 48
EMERGENCY MODE .................................................. 51
SETTING THE MODE DISPLAY - OUTDOOR UNIT 56
CTK04 ADDENDUM .................................................... 65
TROUBLESHOOTING ..................................................... 95
WIRING DIAGRAMS ...................................................... 110
ACCESSORIES.............................................................. 114
T
O
PREVENT
THE
RISK
OF
PROPERTY
DAMAGE
,
PERSONAL
INJURY
,
OR
DEATH
,
DO
NOT
STORE
COMBUSTIBLE
MATERIALS
OR
USE
GASOLINE
OR
OTHER
FLAMMABLE
LIQUIDS
OR
VAPORS
IN
THE
VICINITY
OF
THIS
APPLIANCE
.