Hose/Line HVAC: Service Precautions

Tighten all of the tubing connections as shown in Fastener Tightening Specifications.

Insufficient or excessive torque when tightening may result in the following conditions:
^ Loose joints
^ Deformed joint parts

These conditions may result in refrigerant leakage. Ensure that all of the metal tubing is free of dents or kinks in order to prevent loss of system capacity due to tube restriction.
^ Do not bend the flexible hoses to a radius of less than 4 times the diameter of the hose.
^ Do not allow the flexible hoses to come in contact with the exhaust manifold.
^ Do not allow the hose assembly to twist towards the exhaust manifold during assembly.
^ Inspect the flexible hoses regularly for the following conditions:
- Leaks
- Brittleness

Replace the flexible hoses with new hoses if deterioration or leaking is found.
^ When disconnecting any fitting in the refrigeration system, perform the following steps:
1. Recover the refrigerant.
2. Proceed with caution. Open the fitting very slowly. Keep your hands and face away in order to avoid injury if liquid refrigerant is in the tube.
^ If you notice that pressure is evident when you loosen the fitting, perform the following tasks:
1. Recover the refrigerant.
2. Open the fitting very slowly.
3. keep your hands and face away in order to avoid personal injury if liquid refrigerant is in the tube.
4. If you notice that pressure is evident when you loosen the fitting, perform the following tasks:
4.1. Retighten the fitting.
4.2. Perform the refrigerant recovery again.
This condition may indicate a high side restriction. Repair a high side restriction before charging the A/C system.
^ In the event any refrigerant tube is opened to the atmosphere, immediately cap or tape the tube in order to prevent the entrance of moisture and dirt. Moisture and dirt may cause internal compressor wear or plugged tubes in the following components:
^ The condenser and evaporator core
^ The expansion tubes
^ The compressor inlet screens
^ Use the proper wrenches when making connections on the O-ring fittings. Always back up the opposing fitting using a wrench in order to prevent distortion of the following components:
- The connecting tubes
- The components
^ When connecting the flexible hose connections, hold the following components at the same time in order to prevent twisting the hose assembly out of location during the tightening of the joint:
- The swagged fitting
- The flare nut
- The coupling to which the nut is attached
^ Ensure that the O-rings and the seats are in perfect condition. The following conditions may cause a refrigerant leak:
- A burr
- A piece of dirt
Change the O-rings when you perform this procedure.
^ Do not perform the following procedures on this type of hose:
- Partial hose replacement
- Splicing and clamp replacement
^ For all repairs, warranty and non-warranty, replace the complete hose assembly.