Carrier WeatherMaker 50KCQ A04 Series Service And Maintenance Instructions Download Page 14

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Fig. 18 — CoreMax

Access Port Assembly

Refrigerant System Pressure Access Ports

There are two access ports in each circuit - on the suction tube

and the discharge tube near the compressor. These are brass fit-

tings with black plastic caps. The hose connection fittings are

standard

-in. SAE male flare couplings.

The brass fittings are two-piece High Flow valves, with a re-

ceptacle base brazed to the tubing and an integral spring-closed

check valve core screwed into the base. See Fig. 18. This check

valve is permanently assembled into this core body and cannot

be serviced separately. Replace the entire core body if neces-

sary. Service tools are available from RCD that allow the re-

placement of the check valve core without having to recover

the entire system refrigerant charge. Apply compressor refrig-

erant oil to the check valve core’s bottom O-ring. Install the fit-

ting body and torque to 96 ±10 in. lb (10.9 ± 1 Nm). Do not ex-

ceed 106 in. lb (11.9 Nm) when tightening.

PURON

(R-410A) REFRIGERANT

This unit is designed for use with Puron (R-410A) refrigerant.

Do not use any other refrigerant in this system.
Puron (R-410A) refrigerant is provided in pink (rose) colored cyl-

inders. These cylinders are available with and without dip tubes;

cylinders with dip tubes will have a label indicating this feature.

For a cylinder with a dip tube, place the cylinder in the upright po-

sition (access valve at the top) when removing liquid refrigerant

for charging. For a cylinder without a dip tube, invert the cylinder

(access valve on the bottom) when removing liquid refrigerant.
Because Puron (R-410A) refrigerant is a blend, it is strongly

recommended that refrigerant always be removed from the cyl-

inder as a liquid. Add liquid refrigerant into the system in the

discharge line. If adding refrigerant into the suction line, use a

commercial metering/expansion device at the gage manifold;

remove liquid from the cylinder, pass it through the metering

device at the gage set and then pass it into the suction line as a

vapor. Do not remove Puron (R-410A) refrigerant from the

cylinder as a vapor.

Refrigerant Charge

The amount of refrigerant charge is listed on the unit’s name-

plate. Refer to Carrier Publication,

GTAC2-5 Charging, Recov-

ery, Recycling and Reclamation Training Manual

and the fol-

lowing procedures:
Unit panels must be in place when unit is operating during the

charging procedure. If unit is equipped with a head pressure con-

trol device, bypass it to ensure full fan operation during charging.
Charge checking and adjustments must be made while the sys-

tem is operating in Cooling only.

NO CHARGE:
Use standard evacuation techniques for Puron (R-410A) refrig-

erant. After evacuating system, weigh the specified amount of

refrigerant.

COOLING CHARGING CHARTS

How To Use Cooling Charging Charts

Take the outdoor ambient temperature and read the suction

pressure gage. Refer to chart to determine what suction tem-

perature should be. If suction temperature is high, add refriger-

ant. If suction temperature is low, carefully recover some of the

charge. Recheck the suction pressure as charge is adjusted.

Example:
Model 50KCQ*A04
Outdoor Temperature . . . . . . . . . . . . . . . . . . . . . . . 85°F (29°C)
Suction Pressure. . . . . . . . . . . . . . . . . . . . . .140 psig (965 kPa)
Suction Temperature . . . . . . . . . . . . . . . . . . . . . . . 55°F (13°C)
Refer to Fig. 19-2 1 for cooling charging charts.

Compressors

LUBRICATION
Compressors are charged with the correct amount of oil at the

factory.

1. CoreMax is a registered trademark of Fastest, Inc.

5/8

” HEX

0.47

0°

0.596

1/2-20 UNF RH

1/2

” HEX