US Patent 12017181 Multi-mode air drying system

A compressed air drying system is provided for removing moisture from compressed air. The dryer operates in two modes in response to the demand for compressed air. In a first mode of operation, a refrigeration compressor runs continuously and the speed of a condenser fan is varied to maintain a constant cooling temperature. In a second mode of operation, the refrigeration compressor runs intermittently between on and off periods. As result, the cooling temperature fluctuates during the second mode of operation.