NanoDryerSales.com is your complete source for Nano air dryers and compressed air treatment products. Our knowledgeable sales staff is here to help you find the right Nano product to fit the job and at distributor discount prices. Contact us today Below are Donaldsons top 3 reasons to replace your air dryer 1. Avoid Brake Failure. Heavy-duty on-road trucks rely on compressed air to actuate braking systems and control the brake operation for the truck and trailer. The compressor takes air from the atmosphere which contains moisture that when compressed, may cause total brake system ... Sep 14, 2021 With a traditional mechanical governor, a commercial vehicle air dryer has two fixed set-points that determine when the compressor charges and unloads. When the system pressure is fully charged typically at 130 psi the mechanical governor sends a pressure signal that tells the compressor to unload.