Carrier 024-036, Service Manual, Page: 23 / 41

: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
23
A08083
Fig. 23 – Position of Sensing Bulb
Piston Body Cleaning or Replacement
1. Recover refrigerant from tubing and coil through high flow service
port on suction and discharge lines. Disconnect refrigerant (liquid)
tube from distributor body. (See Fig. 24 .)
2. Avoid damaging seal ring or machined surfaces on piston, bore, and
retainer.
3. Using small wire with a hook on end of it, remove piston from
body.
A10176
Fig. 24 – Refrigerant Flow-Control Device
4. Install new or cleaned piston into body.
5. Replace seal ring on retainer.
6. Reconnect refrigerant tube to piston body.
7. Pressurize tubing and coil, then leak check.
8. Evacuate tubing and coil as necessary.
Liquid Tube Strainer/Filter
The TXV and refrigerant flow-control device is protected by either a
wire mesh strainer or filter drier.
Refrigeration System Repair
Leak Detection
New installations should be checked for leaks prior to complete
charging. If a system has lost all or most of its charge, system must be
pressurized again to approximately 150 psig minimum and 375 psig
maximum. This can be done by adding refrigerant using normal charging
procedures or by pressurizing system with nitrogen (less expensive than
refrigerant). Nitrogen also leaks faster than refrigerants. Nitrogen
cannot, however, be detected by an electronic leak detector. (See
Fig. 25 .)
Table 4 – Piston/TXV Table
Air Conditioner
Unit Size (ton)
Indoor Cooling Piston/TXV
Number
Outdoor
Heating
Piston
Number
13.4 SEER2
24 57 --
30 63 --
36 67 --
42 76 --
48 80 --
60 TXV --
Heat Pump
Unit Size (ton)
Indoor Cooling Piston/TXV
Number
Outdoor
Heating
Piston
Number
13.4 SEER2
24 57 -
30 63 55
36 67 57
42 76 59
48 TXV -
60 TXV 70
WARNING
!
PERSONAL INJURY AND ENVIRONMENTAL HAZARD
Failure to relieve system pressure could result in personal injury and/or
death.
1. Relieve pressure and recover all refrigerant before servicing
existing equipment, and before final unit disposal. Use all
service ports.
2. Federal regulations require that you do not vent refrigerant into
the atmosphere. Recover during system repair or final unit
disposal.
CAUTION
!
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment damage.
Damage may occur to the scroll compressor if operated at a negative
suction pressure during a system pumpdown.
2 O’CLOCK
10 O’CLOCK
SENSING BULB
STRAP
SUCTION TUBE
CAUTION
!
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment damage.
When cleaning the piston orifice, be careful not to scratch or enlarge the
opening, as this will affect operation.
CAUTION
!
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment damage.
Use a backup wrench and do not over tighten, as deformation of the
piston body will occur, causing the piston to lodge in a partially open or
closed position.
WARNING
!
EXPLOSION HAZARD
Failure to follow this warning could result
in death, serious personal injury, and/or
property damage.
Never use air or gases containing oxygen
for leak testing or operating refrigerant
compressors. Pressurized mixtures of air or
gases containing oxygen can lead to an
explosion.
PISTON
PISTON
RETAINER
BRASS
HEX NUT
DISTRIBUTOR
BODY
TEFLON SEAL