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TK 56430-18-IP-EN
Protective Heat Shields
The installation of protective heat shields (installer supplied) is recommended for any exposed refrigeration hoses
located near vehicle heat sources such as the exhaust system. Exhaust temperatures can exceed 1600°F and cause
damage to refrigeration hoses if they are not properly shielded.
Refrigeration hoses need a shield when located within:
•
4.00 in. (102 mm) from engine exhaust manifolds, catalytic converters and mufflers.
•
2.00 in. (51 mm) from exhaust systems under the vehicle.
•
Exhaust systems move with the engine. Always allow for exhaust and engine movement when routing and securing
refrigeration hoses to the engine or chassis.
Figure 46.
Protective heat shield shown next to catalytic converter.
Refrigeration Fittings
Three different types of refrigeration fittings are used on vehicle powered truck units: Tube-O, ORS and Flare. Tube-O
fittings are used only on the compressor, while ORS (O-Ring Seal) fittings are used for the majority of the other
connections. Tube-O and ORS fittings require matching O-Rings (EPDM ONLY!) to seal properly. Flare fittings (not
shown) are connected to the suction splice connector on units equipped with an oil return and/or Jet Cool. These
fittings do not use O-Rings. Tube-O and ORS fittings typically come in male and female ends, straight, 45° and 90°, and
with or without charge ports. Before assembling any hoses, first match the fitting to the component, then match the
hose to the fitting.
N
No
otte
e:: While most fitting sizes match the hose size (i.e., #10 fitting to #10 hose), some #10 Tube-O fittings attach to a #12
hose. Always refer to your unit installation manual for the proper size hoses required for your specific model.
