I've had vehicles where the evaporator fins start growing a moldy film that smells like gym socks worn way too many times. There is an aerosol chemical in a can that can be sprayed into the evaporator case to kill the mold.

Rick

Most vehicles should turn on the radiator electric fan immediately with the A/C turned on to put cooling air through the fins of the condenser. This limits compressor head pressures and aids in cooling the liquid refrigerant as it flows through the condenser. Put a household fan blowing onto the A/C...

Do your fans have a wattage number stamped on them somewhere or maybe online somewhere? If yes, we can derive the amps. Maybe, let's say = 240 watts? 20 amps x 12 volts = 240 watts.

A clamp on ammeter can also measure amperage though maybe less accurately.

Rick

The Haynes Manual for your Chevelle does not list capacities for R12 or its oil. I have it on competent authority (Team Chevelle web site) that a 1970 A-body with a C-60 compressor took 60 ounces of R12. What compressor are you running, C-60 or maybe an A-6? I cannot find a reference for a 1969 A-bo...

Could also be a blend door "air valve" mixing problem in the dash - heater air mixing with cold air.

Rick

I was at 42-43 F here in Louisiana yesterday at about 150-200 feet above sea level. Very humid air in the summer. I think my temps would be a little lower if it was less humid around here but overall, I'm happy at 42 degrees at the center vent of my 70 El Camino running 2000 RPM in a modern R134 sys...

I'm using a Four Seasons Fan Relay kit - part number 35879 - to make one of the E-fans on my 70 Chevy El Camino kick on the instant that the AC compressor clutch engages. This kit has a special compressor wire that overrides the wait time for the engine temperature to kick a fan on. This also helps ...

Its all about the dollars. The manufacturer and the dealerships want you to return and pay for a more expensive repair. Planned obsolescence.

Rick

I would get a set of gauges, a can of refrigerant with oil, maybe with a little dye and top it off. If it is a slow leak and if your compressor can still develop good pressure, I'd run it for at least the upcoming summer season and see what happens. The leak check dye in the can can tell you where t...

You asked: "Why does the company say it will fail and need replacement"? Answer: Because they want your money to replace the parts.

Rick