Carrier 50ET - Manual (Page 9)

HEATING A COOLING
50ET,QT
Single-Package Units
m
AccuRater™ Device (Dual-Piston Type)
Servicing — See Fig. 16 for AccuRater components.
The pistons have a refrigerant metering orifice through
them. The retainers form a stop for the pistons in the
refrigerant bypass mode, and a sealing surface for liquid
line flare connection. To clean or replace piston;
1. Shut off power to unit.
2. Protect area around unit to prevent damage to
interior, furnishings, etc.
3. Remove refrigerant from unit.
4. Remove liquid line flare connections from Accu­
Rater. See Fig. 3 for AccuRater location.
5. Note position of arrow on AccuRater body in
relation to unit.
6. Pull retainer out of body. Be careful not to scratch
flare sealing surface. If retainer does not pull out
easily, carefully use locking pliers to remove
retainer. Replace scratched or damaged retainer.
7. Slide piston out by inserting a small soft wire through
metering hole (18-gage thermostat wire). Check that
metering hole, sealing surface around piston cones
and fluted portion of piston are not damaged.
8. See chart on indoor blower scroll for illustration of
proper arrangement and sizes of pistons.
9. Clean piston refrigerant metering orifice.
10. Replace retainer 0-ring before reassembling Accu­
Rater. Carrier O-ring Part No. is 99CC501052.
LIQUID LINE STRAINERS (protect AccuRater), are
made of wire mesh and located in the liquid line on each
side of the AccuRater. The strainers are pressed into the
line. Remove strainer by threading a #10 sheet metal
screw into strainer and pulling the screw with pliers.
Compressor Removal — (Refer to Fig. 2.)
IMPORTANT: Compressor cannot be removed
from an installed chassis. Remove chassis from
sleeve, then bring to service truck or dealer shop
before removing compressor.
See Table 4 for compressor information. Follow safety
codes and wear safety glasses and work gloves. Have
quenching cloth available.
A CAUTION
Aluminum tubing is used in 50QT coils. Do not
overheat or place excessive strain on tubing or
damage may result.
________________
Table 4 — Compressor Data
MODEL 50ET,QT COMPRESSOR
OIL RECHARGE
(oz)
212
Copeland
RE-Z3-0150-PFV
20
215
Tecumseh
AB5515H
32
218
Bristol
H22B193ABCA
27
224
Copeland
CRD-10200-PFV
51
230
Copeland
CRF1-0250-PFV
51
Compressor Removal — 50ET,QT212,215
I. Shutoff power to unit. Remove chassis indoor cover.
Fig. 1.
Remove chassis to truck or shop.
Remove refrigerant from unit using refrigerant
removal methods described in Carrier Standard
Service Techniques Manual, Chapter 1, Refrigerants.
Remove core from suction and discharge line
Schrader valves.
2
.
3.
4.
FLARE
NUT
STRAINER
TO
INDOOR
COIL
RUBBER 0-RlNG
STAMPED ARROW ON
COUPLING BODY
(TOWARD INDOOR COIL)
50ET
FLARE
NUT
STRAINER
#
STAMPED ARROW ON
COUPLING BODY
RUBBER 0-RING (TOWARD INDOOR COIL)
Fig. 16 — AccuRater Device (Dual-Piston) Components
FLARE
NUT
50QT
Manufacturer reserves the right to discontinue, or change at any time, specitications or designs without notice and without incurring obiigatlons.
Book|1 |1 |4 |4 PC131 Catalog No 535-078 PrintedinUSA Form 50ET.QT-3SI Pg9 5-85 Replaces. 50QT-10SI