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T--311
4--11
Change 07/09
will absorb moisture and become very acid-
ic and corrosive. Mineral oil will not absorb
moisture and thus prevent corrosion.
CAUTION
Always use existing holes in the chassis
frame. Never drill holes in the chassis
frame.
CAUTION
Never secure hoses or harnesses to any
part of the vehicle fuel system.
Install all hoses and fittings in a manner that will not
adversely affect the fitting torque.
4.9
TORQUE SPECIFICATIONS - REFRIGERANT
FITTINGS
All refrigerant hose fitting connections must be torqued
to the specifications listed in Table 4-1. Fittings threads
and O-Rings must be lubricated with mineral oil, not
PAG or POE oils.
Table 4-1 STANDARD TORQUE REQUIREMENTS
SIZE
TUBE O.D. *
FLARE
O-RING
THREAD **
STEEL TUBING
ALUM. TUBING
4
1/4 inch (.250)
11-13 ft./lbs.
30-35 ft./lbs.
5-7 ft./lbs.
7/16
5
3/8 inch (.375)
15-17 ft./lbs.
30-35 ft./lbs.
8-10 ft./lbs
9/16
6
3/8 inch (.375)
18-20 ft./lbs.
30-35 ft./lbs.
11-13 ft./lbs
5/8
8
1/2 inch (.500)
36-39 ft./lbs.
30-35 ft./lbs.
15-20 ft./lbs
3/4
10
5/8 inch (.625)
52-57 ft./lbs.
30-35 ft./lbs.
21-27 ft./lbs
7/8
12
3/4 inch (.750)
71-79 ft./lbs.
30-35 ft./lbs.
28-33 ft./lbs
1-1/16
* The tube O.D. is measured at the point it passes through the nut. ** Thread pitch may vary.
4.10 ROOFTOP CONDENSER HOSE ROUTING
(CM-7 & CM-11)
Always keep hose capped until ready to connect to a
system component.
Hoses should be routed as close to the evaporator as
possible. This will ease the routing through the roof and
to the condenser.
When making condenser connections, always use
caution as you start the fitting onto the condenser.
Lubricate the fitting and “O” Ring with mineral oil before
making the connection.
Properly clamping a fitting to the refrigerant hose is very
important. Do not attempt to attach any hose or fitting
until you have familiarized yourself with Carrier
Transport Air Conditioning Quick-Click hose/fitting
clamping procedures.
4.11
AUXILIARY HEATER HOSE ROUTING
(GENERIC)
Carrier Transport Air Conditioning does not supply
heater hose for connecting to a Carrier Transport Air
Conditioning supplied heater coil.
The following general guidelines have been established
to aid in connecting an auxiliary heater coil to the
vehicles heating system.
Use only approved OEM type heater hose or its
equivalent.
Use only worm-gear drive type hose clamps on heater
hose.
Never secure heater hose to the transmission dip stick
tube or on to any fuel system component.
Do not route heater hoses near sharp edges, utilize
edge guards to protect against cutting and/or chaffing.
Secure heater hoses with insulated P-clamps.
CAUTION
Tie-Wraps may be used to bundle hoses
and harnesses, but should never be used to
secure hoses to the vehicle.
The hot water supply hose should be connected to the
lowest part of the heater core.
Minimize air pockets in the system by adding an air
bleed-off device at the systems high point.
The use of a positive shut-off valve in the auxiliary hot
water supply hose is highly recommended. Any leakage
of hot water into the heater core during the air
conditioning season will adversely effect the cooling
efficiency of the air conditioning system.
4.12 PIPING DIAGRAMS
While all piping diagrams could not be included in this
manual, some of the more common installations have.
Always refer to the detailed piping diagrams furnished
with the system you are installing. If your specific piping
diagram is not included with your system installation kit,
contact the Carrier Transport Air Conditioning Technical
Service Hot Line (1--800-450-2211).