Maintaining Chemical Stability

The chemical stability of the refrigeration system plays an important role in the efficient operation and longevity of the A/C system.
When air, moisture or particulate contamination are introduced into the refrigeration system, the following results will occur:
^ The chemical stability of R-134a and polyalkylene glycol (PAG) synthetic lubricant will change.
^ The pressure/temperature symmetry will change.
^ The A/C system efficiency will be diminished.
^ Internal A/C system parts may corrode and/or wear in an abnormal manner.

Use the following general practices to maintain chemical stability in the refrigeration system:
^ Wipe away dirt and/or oil before you break a refrigerant connection. This will reduce the possibility of particulate contamination.
^ Cap, plug or tape both sides of an open connection as soon as possible. This will minimize the amount of dirt and moisture entering the system.
^ Ensure that the following remain clean and dry:
- The tools being used for the repair
- The surrounding area of the repair
- The hoses and connectors for the ACR4 machine or manifold gage set
- The replacement parts
^ When adding polyalkylene glycol (PAG) lubricant, ensure the transfer device and the container remain clean and dry to minimize moisture intrusion.
^ Do not leave the A/C system open any longer than necessary.
^ Before recharging an A/C system that has been opened, properly evacuate and vacuum test the system.
^ Service parts are dehydrated and sealed prior to shipping. Retain the parts in their sealed packages until you are ready to use them.
^ Ensure the parts are at room temperature before opening the packages. This prevents condensation on the parts from humidity in the atmosphere.
^ Attach the A/C service equipment quick-connects as soon as possible after removing the service caps.