R-12 Systems

Testing the system for leaks is one of the most important phases of A/C system troubleshooting. The following methods will prove useful in detecting leaks or checking connections if service work has been performed. Before beginning any leak test, attach a manifold gauge set and note pressure. If little or no pressure is indicated, a partial charge must be installed. Check all connections, compressor head gasket, oil filler plug and compressor shaft seal for leaks.