Re: Aftermarket Air Conditioning

Posted by DavidPackard On 2023/7/9 22:34:30

TxGoat; The web seems to think 3-5 horsepower is the range for AC compressors. As a first estimate the power should vary by speed cubed, and torque by speed squared, so if the 3-5 hp is for a higher rpm then at idle speeds the load is quite small. That by itself may explain why the compressor clutch in my ’54 functions so well, that is the Packard engine speed is quite low therefore the torque never reaches the design point of the clutch, and the fact that the current is essentially ½ of the design current the Packard’s slowness still wins the day.

Howard; The ‘under dash’ evaporator design places the unit essentially in your lap, with little or no duct loss. Perhaps in that configuration a low fan speed still results in acceptable air flow. In the unit featured in the video my bet is all of the controls are hidden under the added panels. The speed switch is set to medium (perhaps at higher speeds an in-line fuse complained), the temperature control set to maximum cooling (minimum temperature), and the single switch is controlling the power to both the blower motor and clutch (open loop unless there’s low & high pressure switchs). Note in the video there is little fan noise. Perhaps an e-mail to Vintage Air is in order.

dp