Carrier 38YCC Series Instructions and recipes

38YCC, 38YCG, 38YCS
10 SEER Split-System
Heat Pump
Installation and Start-Up Instructions
NOTE: Read the entire instruction manual before starting the
installation.
This symbol →indicates a change since the last issue.
SAFETY CONSIDERATIONS
Improper installation, adjustment, alteration, service, maintenance,
or use can cause explosion, fire, electrical shock, or other
conditions which may cause death, personal injury, or property
damage. Consult a qualified installer, service agency, or your
distributor or branch for information or assistance. The qualified
installer or agency must use factory-authorized kits or accessories
when modifying this product. Refer to the individual instructions
packaged with the kits or accessories when installing.
Follow all safety codes. Wear safety glasses, protective clothing,
and work gloves. Use quenching cloth for brazing operations.
Have fire extinguisher available. Read these instructions thor-
oughly and follow all warnings or cautions included in literature
and attached to the unit. Consult local building codes and National
Electrical Code (NEC) for special requirements.
Recognize safety information. This is the safety-alert symbol .
When you see this symbol on the unit and in instructions or
manuals, be alert to the potential for personal injury.
Understand the signal words DANGER, WARNING, and CAU-
TION. These words are used with the safety-alert symbol. DAN-
GER identifies the most serious hazards which will result in severe
personal injury or death. WARNING signifies hazards which
could result in personal injury or death. CAUTION is used to
identify unsafe practices which would result in minor personal
injury or product and property damage. NOTE is used to highlight
suggestions which will result in enhanced installation, reliability,
or operation.
Before installing, modifying, or servicing system, main elec-
trical disconnect switch must be in the OFF position. There
may be more than 1 disconnect switch. Lock out and tag
switch(es) with a suitable warning label. Electrical shock can
cause personal injury or death.
INTRODUCTION AND RECOMMENDATIONS
NOTE: In some cases noise has been traced to improper instal-
lation of equipment.
1. Locate unit away from windows, patios, decks, and so forth
where unit operation sounds may disturb customer.
2. Ensure that vapor- and liquid-tube diameters are appropriate to
capacity of unit.
3. Run refrigerant tubes as directly as possible by avoiding
unnecessary turns and bends.
4. Leave some slack between structure and unit to absorb
vibration.
5. When passing refrigerant tubes through the wall, seal opening
with RTV or other pliable silicon-based caulk. (See Fig. 3.)
6. Avoid direct refrigerant tubing contact with water pipes, duct
work, floor joists, wall studs, floors, and walls.
7. Do not suspend refrigerant tubing from joists and studs with a
rigid wire or strap that comes in direct contact with tubing.
(See Fig. 3.)
8. Ensure that refrigerant tubing insulation is pliable and com-
pletely surrounds vapor tube.
9. When necessary, use hanger straps which are 1 in. wide and
conform to shape of tubing insulation. (See Fig. 3.)
10. Isolate hanger straps from insulation by using metal sleeves
bent to conform to shape of insulation.
Fig. 1—Model 38YCC
A97005
Fig. 2—Models 38YCG and 38YCS
A98525
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Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book 1 4
Tab 5a 5a PC 101 Catalog No. 533-80100 Printed in U.S.A. Form 38YCC-6SI Pg 1 5-03 Replaces: 38YCC-5SI

When outdoor unit is connected to factory-approved indoor unit,
outdoor unit contains system-refrigerant charge for operation with
indoor unit of the same size when connected by 15 ft of
field-supplied or factory-accessory tubing. For proper unit opera-
tion, check refrigerant charge using charging information located
on control-box cover and/or in the Check Charge section of this
Instruction.
IMPORTANT: Maximum liquid-line size is 3/8-in. O.D. for all
residential applications including long line applications.
IMPORTANT: Always install a liquid-line filter drier on any
system using an existing field service lineset and/or existing indoor
coil. Also, always use liquid line filter driers on burnout compres-
sor replacments. Refer to Product Data Digest for appropriate part
number. Obtain filter drier from your distributor or branch.
INSTALLATION
Step 1—Check Equipment and Job Site
UNPACK UNIT
Move to final location. Remove carton, taking care not to damage
unit.
INSPECT EQUIPMENT
File claim with shipping company prior to installation if shipment
is damaged or incomplete. Locate unit-rating plate on unit-service
panel. It contains information needed to properly install unit.
Check rating plate to be sure unit matches job specifications.
Step 2—Install on a Solid, Level Mounting Pad
If conditions or local codes require the unit be attached to pad,
tie-down bolts should be used and fastened through knockouts
provided in unit base pan. Refer to unit-mounting pattern in Fig. 4
to determine base-pan size and knockout-hole location.
On rooftop applications, mount on level platform or frame 6 in.
above roof surface. Place unit above a load-bearing wall and
isolate unit and tubing set from structure. Arrange supporting
members to adequately support unit and minimize transmission of
vibration to building. Consult local codes governing rooftop
applications.
Roof-mounted units exposed to winds above 5 mph may require
wind baffles to achieve adequate defrost. Consult Low-Ambient
Guideline for wind-baffle construction.
NOTE: Unit must be level to within ±2° (±3/8 in./ft) per
compressor manufacturer specifications.
Step 3—Clearance Requirements
When installing, allow sufficient space for airflow clearance,
wiring, refrigerant piping, and service. Allow 30-in. clearance to
service end of unit and 48 in. above unit. For proper airflow, a 6-in.
clearance on 1 side of unit and 12 in. on all remaining sides must
be maintained. Maintain a distance of 24 in. between units.
Position so water, snow, or ice from roof or eaves cannot fall
directly on unit.
On rooftop applications, locate unit at least 6 in. above roof
surface.
Step 4—Operating Ambients
The minimum outdoor-operating ambient in cooling mode is 55°F,
and the maximum outdoor-operating ambient in cooling mode is
125°F. The maximum outdoor-operating ambient in heating mode
is 66°F.
Step 5—Elevate Unit
Accumulation of water and ice in base pan may cause
equipment damage.
In areas where prolonged freezing temperatures are encountered,
elevate unit per local climate and code requirements to provide
clearance above estimated snowfall level and ensure adequate
drainage of unit.
Step 6—Check Indoor And Outdoor AccuRater® Piston
Check indoor-coil piston to see if it matches the required piston
shown on outdoor unit-rating plate. If it does not match, replace
indoor-coil piston with piston shipped with outdoor unit. The
piston shipped with outdoor unit is correct for any approved
indoor-coil combination.
Fig. 3—Connecting Tubing Installation
A94028
INSULATION
VAPOR TUBE
LIQUID TUBE
OUTDOOR WALL INDOOR WALL
LIQUID TUBE
VAPOR TUBE
INSULATION
CAULK
Avoid contact between tubing and structureNOTE:
THROUGH THE WALL
HANGER STRAP
(AROUND VAPOR
TUBE ONLY)
JOIST
1″MIN.
SUSPENSION
Fig. 4—Mounting Unit to Pad
Dimensions (In.)
UNIT
SIZE
MINIMUM
MOUNTING-PAD
DIMENSIONS
TIEDOWN KNOCKOUT LOCATIONS
ABC
018–030 22-1/2 x 22-1/2 3-11/16 18-1/8 14-3/8
036–060 30 x 30 6-1/2 23-1/2 20
A94199
C
B
A
3⁄8″D. (9.53) TIEDOWN
KNOCKOUTS (2) PLACES
2
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To avoid equipment damage and/or loss of performance
remove indoor-coil piston if unit is to be installed on system
with a TXV-metering device.
Step 7—Check Defrost Thermostat
Check defrost thermostat to ensure it is properly located and
securely attached. There is a liquid header with a brass distributor
and feeder tube going into outdoor coil. At the end of 1 of the
feeder tubes, there is a 3/8-in. O.D. stub tube approximately 3 in.
long. The defrost thermostat should be located on stub tube. Note
that there is only 1 stub tube used with liquid header, and on most
units it is the bottom circuit.
Step 8—Make Piping Connections
Relieve pressure and recover all refrigerant before system
repair or final unit disposal to avoid personal injury or death.
Use all service ports and open all flow-control devices,
including solenoid valves.
If ANY refrigerant tubing is buried, provide a 6 in. vertical
rise at service valve to avoid equipment damage. Refrigerant
tubing lengths up to 36 in. may be buried without further
special consideration. For lengths above 36 in., consult your
local distributor.
To prevent damage to unit or service valves observe the
following:
•Use a brazing shield.
•Wrap service valves with wet cloth or use a heat-sink
material.
Outdoor units may be connected to indoor section using accessory-
tubing package or field-supplied refrigerant-grade tubing of cor-
rect size and condition. For tubing requirements beyond 50 ft
length or 20 ft vertical differential, substantial capacity and
performance losses can occur. Following the recommendations in
the Residential Split-System Long-Line Application Guideline
will reduce these losses. Refer to Table 1 for field-tubing diam-
eters.
REFRIGERANT TUBING
Connect tubing to fittings on outdoor unit vapor- and liquid-
service valves. (See Table 1.) Use refrigerant-grade tubing. Refer
to appropriate section below for type of service valves installed on
unit.
SWEAT CONNECTION
To avoid valve damage while brazing, service valves must be
wrapped in a heat-sinking material such as a wet cloth.
1. Remove plastic retainer holding outdoor piston in liquid-
service valve.
2. Locate adapter tube shipped with unit.
3. Install strainer in adapter tube and connect tube to service
valve. (See Fig. 5.)
4. Connect refrigerant tubing to fittings on outdoor-unit vapor-
and liquid-service valves.
5. Service valves are closed from factory and ready for brazing.
After wrapping service valve with a wet cloth, tubing set can
be brazed to service valve using either silver-bearing or
non-silver-bearing brazing material. Do not use soft solder
(material that melts below 800°F). Consult local code require-
ments.
Refrigerant tubing and indoor coil are now ready for leak testing.
This check should include all field and factory joints.
FINAL TUBING CHECK
IMPORTANT: Check to be certain factory tubing on both indoor
and outdoor unit has not shifted during shipment. Ensure tubes are
not rubbing against each other or any sheet metal. Pay close
attention to feeder tubes, making sure wire ties on feeder tubes are
secure and tight.
Table 1—Refrigerant Connections and Recommended Liquid- and Vapor-Tube Diameters (In.)
UNIT
SIZE LIQUID VAPOR VAPOR (LONG LINE)
Connection Diameter Tube Diameter Connection Diameter Tube Diameter Connection Diameter Tube Diameter
018, 024 3/8 3/8 3/4 3/4 3/4 3/4
030, 036 3/8 3/8 3/4 3/4 3/4 7/8
042, 048 3/8 3/8 7/8 7/8 7/8 1-1/8
060 3/8 3/8 7/8 1-1/8 7/8 1-1/8
NOTES:
1. Tube diameters are for lengths up to 50 ft or 20 ft vertical differential. For tubing lengths greater than 50 ft, consult Long Line section of the Application Guideline.
2. Do not apply capillary-tube indoor coils to these units.
Fig. 5—Liquid-Service Valve with Sweat-Adapter
Tube
A97512
PISTON BODY
PISTON
PISTON
RETAINER
SWEAT/FLARE ADAPTER
STRAINER
3
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Step 9—Make Electrical Connections
To avoid personal injury or death, do not supply power to unit
with compressor terminal-box cover removed.
Be sure field wiring complies with local and national fire, safety,
and electrical codes, and voltage to system is within limits shown
on unit-rating plate. Contact local power company for correction of
improper voltage. See unit-rating plate for recommended circuit-
protection device.
NOTE: Operation of unit on improper line voltage constitutes
abuse and could affect unit reliability. See unit-rating plate. Do not
install unit in system where voltage or phase imbalance (3 phase)
may fluctuate above or below permissible limits.
NOTE: Use copper wire only between disconnect switch and
unit.
NOTE: Install branch-circuit disconnect of adequate size per
NEC to handle unit-starting current. Locate disconnect within sight
from and readily accessible from unit, per Section 440-14 of NEC.
ROUTE GROUND AND POWER WIRES
Remove access panel and control box to gain access to unit wiring.
Extend wires from disconnect through power-wiring hole provided
and into unit-control box.
The unit cabinet must have an uninterrupted or unbroken
ground to minimize personal injury if an electrical fault
should occur. The ground may consist of electrical wire or
metal conduit when installed in accordance with existing
electrical codes. Failure to follow this warning can result in an
electric shock, fire, or death.
CONNECT GROUND AND POWER WIRES
Connect ground wire to ground connection in control box for
safety. Connect power wiring to contactor as shown in Fig. 6.
CONNECT CONTROL WIRING
Route 24v control wires through control-wiring grommet and
connect leads to control wiring. Refer also to Installation Instruc-
tions packaged with thermostat.
Use No. 18 AWG color-coded, insulated (35°C minimum) wire. If
thermostat is located more than 100 ft from unit, as measured
along the control-voltage wires, use No. 16 AWG color-coded
wire to avoid excessive voltage drop.
All wiring must be NEC Class 1 and must be separated from
incoming power leads.
Use furnace transformer, fan-coil transformer, or accessory trans-
former for control power, 24v/40va minimum.
NOTE: Use of available 24v accessories may exceed the mini-
mum 40va power requirement. Determine total transformer load-
ing and increase the transformer capacity or split the load with an
accessory transformer as required.
FINAL WIRING CHECK
IMPORTANT: Check factory wiring and field-wire connections
to ensure terminations are secured properly. Check wire routing to
ensure wires are not in contact with tubing, sheet metal, and so
forth.
Step 10—Compressor Crankcase Heater
When equipped with a crankcase heater, furnish power to heater a
minimum of 24 hr before starting unit. To furnish power to heater
only, set thermostat to OFF and close electrical disconnect to
outdoor unit. A crankcase heater is required if refrigerant tubing is
longer than 50 ft.
Step 11—Install Electrical Accessories
Refer to the individual instructions packaged with kits or acces-
sories when installing.
Step 12—Start-Up
To prevent compressor damage or personal injury, observe
the following:
•Do not overcharge system with refrigerant.
•Do not operate unit in a vacuum or at negative pressure.
•Do not disable low-pressure switch.
In scroll compressor applications:
•Dome temperatures may be hot.
To prevent personal injury wear safety glasses, protective
clothing, and gloves when handling refrigerant and observe
the following:
•Back-seating service valves are not equipped with Schrader
valves. Fully back seat (counterclockwise) valve stem before
removing gage-port cap.
•Front-seating service valves are equipped with Schrader
valves.
Federal regulations require that you do not vent refrigerant to
atmosphere. Recover during system repair or final unit
disposal.
If refrigerant tubes or indoor coil are exposed to atmosphere, they
must be evacuated to 500 microns to eliminate contamination and
moisture in the system.
Follow these steps to properly start up the system:
1. Fully back seat (open) liquid- and vapor-tube service valves.
2. Unit is shipped with valve stem(s) front seated (closed) and
caps installed. Replace stem caps after system is opened to
refrigerant flow. Replace caps finger-tight and tighten with
wrench an additional 1/12 turn.
3. Close electrical disconnects to energize system.
4. Set room thermostat to desired temperature. Be sure set point
is below indoor ambient temperature.
Fig. 6—Line Power Connections
A94025
DISCONNECT
PER N.E.C. AND/OR
LOCAL CODES CONTACTOR
GROUND
LUG
FIELD GROUND
WIRING
FIELD POWER
WIRING
BLUE
3 PHASE ONLY
4

5. Set room thermostat to HEAT or COOL and fan control to ON
or AUTO mode, as desired. Operate unit for a minimum of 15
minutes. Check system-refrigerant charge.
To avoid equipment damage ensure compressor rotation is
correct.•3-phase scroll compressors are rotation sensitive.
•A flashing LED on phase monitor indicates reverse rotation.
(See Fig. 8 and Table 2.)
This will not allow contactor to be energized.
•Disconnect power to unit and interchange 2 field-wiring
leads on unit contactor.
Step 13—Check Charge
Factory charge is shown on unit-rating plate. To check charge in
cooling mode, refer to Cooling-Only Procedure on unit wiring and
charging label.
COOLING-ONLY PROCEDURE
NOTE: If superheat- or subcooling-charging conditions are not
favorable, charge must be weighed in accordance with unit-rating
plate ±0.6 oz/ft of 3/8-in. liquid line above or below 15 ft
respectively.
EXAMPLE:
To calculate additional charge required for a 25-ft line set:
25 ft – 15 ft = 10 ft X 0.6 oz/ft=6ozofadditional charge
HEATING CHECK-CHART PROCEDURE
To check system operation during heating cycle, refer to the
Heating Check Chart on outdoor unit. This chart indicates whether
a correct relationship exists between system operating pressure and
air temperature entering indoor and outdoor units. If pressure and
temperature do not match on chart, system-refrigerant charge may
not be correct. Do not use chart to adjust refrigerant charge.
NOTE: When charging is necessary during heating season,
charge must be weighed in accordance with unit rating plate ±0.6
oz/ft of 3/8-in. liquid line above or below 15 ft respectively.
Step 14—Final Checks
IMPORTANT: Before leaving job, be sure to do the following:
1. Securely fasten all panels and covers.
2. Tighten service valve-stem caps to 1/12-turn past finger-tight.
3. Leave User’s Manual with owner. Explain system operation
and periodic maintenance requirements outlined in manual.
4. Fill out Dealer Installation Checklist and place in customer
file.
SEQUENCE OF OPERATION
With power supplied to indoor and outdoor units, transformer is
energized.
Cooling
On a call for cooling, thermostat makes circuits R-O, R-Y, and
R-G. Circuit R-O energizes reversing valve, switching it to cooling
position. On 3-phase models with scroll compressors, the units are
equipped with a phase monitor to detect if the incoming power is
correctly phased for compressor operation. If phasing is correct,
circuit R-Y energizes contactor, starting outdoor-fan motor and
compressor circuit. R-G energizes indoor unit-blower relay, start-
ing indoor-blower motor on high speed.
Fig. 7—Generic Wiring Diagram
(See Thermostat Installation Instructions
for wiring specific unit combinations.) A02325
24 VAC HOT R
C
W2
Y
G
R
C
RVS COOLING
C
W2
HP THERMOSTAT TYPICAL
FAN COIL HEAT
PUMP
G
O
E
W2
E
W3
R
Y
24 VAC COM
HEAT STAGE 2
COOL/HEAT
STAGE 1
INDOOR FAN
EMERGENCY
HEAT
O
*
*
*
IF AVAILABLE
*
LEGEND
24-V FACTORY WIRING
24-V FIELD WIRING
FIELD SPLICE CONNECTION
OUTDOOR THERMOSTAT
EMERGENCY HEAT RELAY
SUPPLEMENTAL HEAT RELAY
SHR
EHR
ODT
5
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NOTE: If the phasing is incorrect, the contactor will not be
energized. To correct the phasing, interchange any 2 of the 3
power connections on the field side.
When thermostat is satisfied, its contacts open, de-energizing the
contactor and blower relay. Compressor and motors should stop.
NOTE: If indoor unit is equipped with a time-delay relay circuit,
the blower runs an additional 90 sec to increase system efficiency.
Heating
On a call for heating, thermostat makes circuits R-Y and R-G. If
phasing is correct, circuit R-Y energizes contactor, starting
outdoor-fan motor and compressor. Circuit R-G energizes indoor-
blower relay, starting blower motor on high speed.
Should temperature continue to fall, R-W2 is made through
second-stage room thermostat. Circuit R-W2 energizes relays,
bringing on supplemental electric heat. If outdoor thermostat is
used (field-installed option), only the first bank will be energized.
Remaining bank of supplemental electric heat will be energized
when outdoor temperature falls below outdoor thermostat setting.
When thermostat is satisfied, its contacts open, de-energizing
contactor and relays. All heaters and motors should stop.
Defrost
The defrost control is a time/temperature control which includes a
field-selectable (quick-connects located at board edge) time period
between defrost cycles (30, 50, or 90 minutes), factory set at 90
minutes.
Defrost mode is identical to cooling mode except that outdoor-fan
motor stops and second-stage heat is turned on to continue
warming conditioned space.
Initially the defrost cycle timer starts when the contactor is
energized and a 24v signal is present on the T1 terminal. Then the
defrost cycle begins when the cycle timer times out (30, 50, 90
min) and the defrost thermostat is closed.
To initiate defrost, the defrost thermostat must be closed. This can
be accomplished as follows:
1. Turn off power to outdoor unit.
2. Disconnect outdoor-fan motor lead from OF2 on control
board. (See Fig. .) Tape lead to prevent grounding.
3. Restart unit in heating mode, allowing frost to accumulate on
outdoor coil.
4. After a few minutes in heating mode, liquid-line temperature
should drop below closing point of defrost thermostat (ap-
proximately 30°F).
5. Short between speed-up terminals with a flat-bladed screw-
driver. (See Fig. 9.) This reduces the timing sequence to
1/256th of original time. (See Table 3.)
6. When you hear reversing valve change position, remove
screwdriver immediately; otherwise, control will terminate
normal 10-minute defrost cycle in approximately 2 sec.
Fig. 8—Phase-Monitor Control
Table 2—Phase-Monitor LED Indicators
LED STATUS
OFF No call for compressor
operation
FLASHING Reversed phase
ON Normal
A00010
Fig. 9—Defrost Control
Table 3—Defrost Control Speedup-Timing
Sequence
PARAMETER MINIMUM
(MINUTES) MAXIMUM (MINUTES) SPEEDUP (NOMINAL)
30–minute cycle 27 33 7 sec
50–minute cycle 45 55 12 sec
90–minute cycle 81 99 21 sec
10–minute cycle 9 11 2 sec
5 minutes 4.5 5.5 1 sec
A02001
R8
OF1 K1
O1
R21
C2
R6
H9C1
C US
®
R14 R13
D13
R7
C4
C10
JW2
JW1
D3
C16
C7
R28
D6
JW3
C13
R4
R1 R2 R3 R11 R5
R26
D1 D2
D10
A29
R9 D4
C19 C9
C1
C5
K2
OF2
CEBD430524-01A 5501A
P2
1Y
T1 C C O
O
DFT
SPEEDUP
P1
1
J1 1
P3
1J2
30 50 90 W1
R20
1
HK32EA001
C17
U1
1
U3
R
W2
Y
C
6
→
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NOTE: Length of defrost cycle is dependent upon length of time
it takes to remove screwdriver from test pins after reversing valve
has shifted.
7. Unit will remain in defrost for remainder of defrost-cycle time
or until defrost thermostat reopens at approximately 80°F coil
temperature of liquid line.
8. Turn off power to outdoor unit and reconnect fan-motor lead
to OF2 on control board. (See Fig. 9.)
CARE AND MAINTENANCE
For continuing high performance and to minimize possible equip-
ment failure, periodic maintenance must be performed on this
equipment.
Frequency of maintenance may vary depending upon geographic
areas, such as coastal applications.
7

Copyright 2003 CARRIER Corp. • 7310 W. Morris St. • Indianapolis, IN 46231 38ycc6si
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book 1 4
Tab 5a 5a PC 101 Catalog No. 533-80100 Printed in U.S.A. Form 38YCC-6SI Pg 8 5-03 Replaces: 38YCC-5SI