Carrier 38AUZ Series - Evacuation and Dehydration; Install Accessories; Complete Electrical Connections

10
Factory
High-Flow
A
ccess Port
Service Valve
with Stem Cap
Field Service
Access Port
(Schrader core)
Sweat
Connection
C10203
Fig. 7 -- Typical Piping Connection Assembly
Evacuation/Dehydration —
Evacuate and dehydrate the c onnected refrigeration
system(s) (excl uding the 38AUZ unit) to 500 microns
using a two-stage vacuum pump attached to the service
ports outside the 38AU service valves, following
description in GTAC II, Module 4, System Dehydration.
UNIT OPERATION AND SAFETY HAZARD
Failure to follow this warning could cause personal
injury, death and/or equipment damage.
Puron
R
(R--410A) refrigerant systems operate at
higher pressure than standard R--22 systems. Do not
use R--22 service equipment or components on Puron
refrigerant equipment.
!
WARNING
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 cylinders. These cyli nders are available with and
without dip tubes; cylinders with dip tubes will have a
labe l indicating this feature. For a cylinder with a dip
tube, place the cylinder in the upright position (access
valve at the top) when removing liquid refrige rant 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
cylinder as a liquid. Admit liquid refrigerant into the system
in the discharge line. If addin g ref rig eran t into the suction
line, use a commercial metering/exp ansion device at the
gauge manifold; remove liquid from the cylinder , pass it
through the metering device at the gauge set and then pass it
into the suctio n line as a vapor. Do not remove Pur on
(R--410A) refrigerant from the cylinder as a vapor .
Preliminary Charge —
Before starting the unit, charge R-410A liquid refrigerant
into the high side of each 38AU circuit through the liquid
service valve(s). The amount of refrigerant added must be
at least 80% of the operating charge listed in Table 3 for
LINEAR line length LESS the factory charge quantity (if
factory shipping charge has not been removed). See
example below.
Allow high and low side pressures to equalize. If pressures
do not equalize readily, charge R-410A vapor (using spe-
cial service manifold with expansion device) into the suc-
tion li ne service port for the low side of system to assure
charge in the evaporator. Refer to GTAC II, Module 5,
Charging, Recover, Rec ycling, and Reclamation for liquid
charging procedures.
Example:
38AUZ*08 (RTPF)
60-ft (18.3 m) linea r line length
Equivalent line length 90-ft (27.4 m)
Liquid Lift: 20-ft (6.1 m)
Select line sizes from Table 3 (38AUZ):
Liquid
1
/
2
in
Suction 1
1
/
8
in.
Charge 22.5 lbs (a t 75--ft linear length)
80% of Operating Charge:
0.80 x 22.5 = 18 lbs
Factory Shipping Charge: 14 lbs
Field-Charge quantity: 18 -- 14 = 4 lbs
For li near line lengths longer than 125 ft (38 m), contact
your local Carri er representative for system charge value.
Step 7 — Install Accessories
Accessories requiring modificati ons to unit wiring should
be completed now. These accessories may include Winter
Start controls and Low Ambient controls. Refer to the
instructions shipped with the accessory.
Step 8 — Complete Electrical Connections
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal
injury or death.
Do not use gas piping as an electrical ground. Unit
cabinet must have an uninterrupted, unbroken electrical
ground to minimize the possibility of personal injury if
an electrical fault should occur . This ground may consist
of electrical wire connected to unit ground lug in control
compartment, or conduit approved for electrical ground
when installed in accordan ce with NEC (Natio n al
Electrical Code); ANS I/N FPA 70, latest edition (in
Canad a, Can ad ian Electrical Cod e CSA [Can adian
Stan dar ds Ass ociatio n] C2 2 .1), and local electrical
codes.
!
WARNING
NOTE: Check all factory and field electrical connections
for tightness. Field-supplied wiring shall conform with the
limitations of 63F(33C) rise.
38AU