Carrier 38BYC Installation And Start-Up Instructions

4. Position sensing bulb on horizontal portion of suction tube
adapter. Secure using supplied hardware.
5. Insulate bulb after installation. (See Fig. 5.)
6. Leak check all connections.
FAN COILS
If indoor unit (fan coil) comes factory equipped with a bi-flow
hard shutoff TXV, no TXV change is required.
If TXV installation is required, refer to TXV kit Installation
Instructions for details on TXV installation.
Step 7—Check Outdoor AccuRater® Piston
Check outdoor unit piston as follows:
1. Remove cap and retainer holding outdoor piston in liquid
service valve.
2. Remove outdoor piston and check size with matching number
on unit rating plate.
3. After verifying size, reinstall piston and retainer. If O-ring is
damaged during removal, install new retainer.
Step 8—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. OD stub tube approximately 2 in.
long. (See Fig. 6.) 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 9—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. Refrigerant tubing lengths up to 36 in.
may be buried without further special consideration. For
lengths above 36 in., refer to Residential Split System
Buried-Line Application Guideline.
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 correct
size and condition. For tubing requirements beyond 50 ft, substan-
tial 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 diameters. Refer to Table 2 for accessory require-
ments.
For buried-line applications greater than 36 in., refer to Table 2
and Residential Split System Buried-Line Application Guideline.
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.
OUTDOOR UNIT CONNECTED TO FACTORY-APPROVED
INDOOR UNIT
Outdoor unit contains correct system refrigerant charge for opera-
tion with indoor unit of same size when connected by 15 ft of
field-supplied or factory-accessory tubing. Check refrigerant
charge for maximum efficiency.
REFRIGERANT TUBING
Connect tubing to fittings on outdoor unit vapor and liquid service
valves. (See Table 1.) Use refrigerant grade tubing.
Fig. 4—Typical TXV Installation
A88382
THERMOSTATIC
EXPANSION
VALVE
EQUALIZER
TUBE
SENSING
BULB
COIL
Fig. 5—Positioning of Sensing Bulb
A81032
2 O'CLOCK
10 O'CLOCK
SENSING BULB
STRAP
SUCTION TUBE
8 O'CLOCK
4 O'CLOCK
7
⁄
8
IN. OD & SMALLER
LARGER THAN
7
⁄
8
IN. OD
Fig. 6—Defrost Thermostat Location
A97517
FEEDER TUBE
DEFROST
THERMOSTAT
STUB TUBE
3
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Carrier 38BYC Specifications

General

Brand	Carrier
Model	38BYC
Category	Heat Pump
Language	English