Carrier 38QE - Manual (Page 14)

ice ports are provided on the liquid and vapor service
valves. Schrader fittings are also provided on the suction
and discharge tubes within the compressor section. Dial-A-
Charge charging cylinder is an accurate device for recharg­
ing systems by weight.
A WARNING
Outdoor section service valve gauge ports are not
equipped with schrader valves. To prevent personal
injury, make sure gauge manifold or port caps are con­
nected to the valve gauge ports before moving valves
off fully backseated position. Wear safety glasses and
gloves when handling refrigerant.
A CAUTION
Evacuate and purge BOTH suction and discharge
Schraders of COMPRESSOR SECTION. Purging only
from one or from only the outdoor service valves may
result in refrigerant being isolated in indoor section due
to system refrigerant control valving.
A CAUTION
Compressor damage may occur if system is over­
charged. Weigh-in all refrigerant.
Initial system charging
The outdoor units are shipped with the base system refrig­
erant charge for correct operation with a total piping length
from indoor section to outdoor section of 25 ft. The remain­
ing components of the system should be leak-checkefl and
evacuated or purged before opening the service valves at
the outdoor cod. The procedure described here should be fol­
lowed for the initial charge:
1. Pressurize the remaining system with R-22 vapor to
100 psig.
A WARNING
Never use oxygen or other flammable gases in a refrig­
eration system for leak checking or any other purpose.
Personal injury or death can result from doing so.
After refrigeration system has been pressurized, with
the appropriate gas, to 100 psig, inspect all compo­
nents, solder joints, mechanical connections, etc., for
leakage.
3. If a leak is found, do not attempt to repair until all
pressure has been reheved from the system. After the
pressure has been reheved, make repairs to leaking
component, repressurize system to 100 psig and con­
tinue leak checking.
4. After ah components, solder joints, mechaniceJ connec­
tions, etc. have been leak-checked, reheve ah system
pressure and evacuate or purge system.
NOTE: If either refrigerant tubing or unit piping is exposed
to atmospheric conditions for longer than 5 minutes, it must
be evacuated to 1000 microns to eliminate contamination
and moisture in the system.
5. Slowly open (turn clockwise) both service valves on the
outdoor fan coil section allowing the bare system
refrigerant cheuge to be released throughout the sys­
tem. Service valves should be fuhy opened and back
seated. Port caps mstahed tightly.
6. Unit is shipped with valve stem(s) frontseated, and
caps installed. Replace stem caps after system is
opened to refrigerant flow (backseated). Replace caps
finger tight and tighten additional 1/12 turn (20-ft lbs
torque) using a backup wrench on valve body flats to
prevent distortion of sheet metal.
7. See refrigerant charging instructions or charging label
of outdoor or compressor section for field charge
adjustment for piping lengths used.
Full charge replacement
If refrigerant escapes from the system, leak test and evacu­
ate entire system. Fohow precautions hsted in initial system
charging. Weigh-in system base charge plus adjustment for
field piping. Refer to charging label on outdoor or compres­
sor section.
System Startup
A WARNING
DO NOT attempt to manually operate the contactor for
any reason. PersoneJ injury can result.
NOTE: The 38QE system compressor section is equipped
with a crankcase heater. It is recommended that the heater
be energized 24 hours prior to starting the unit. To energize
crankcase heater set thermostat mode swritches to “off,”
turn on power to compressor section to the indoor fan coU
and thermostat.
Refer to the HydroTech 2000 Start-up and Service Manual
for further instructions before operating system. Leave the
thermostat mode switches to ‘OFF’ position until the start­
up instructions have bjgen>thoroughly and completely read
and proper system op®E&on has been confirmed.
Copyright 1990 Carrier Corporation
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
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PC 101 Catalog No. 563-964 Printed in U.S.A. Form 38QE-3SI Pg 14 , 5-90 Repiaces: 38QE-2Si
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