08Air Brake System Cold Weather Operation Tips130012202018 TECH Tips Air Brake System - Cold Weather Operation Tips As the cold weather approaches, operators and fleets alike begin to look to their vehicles with an eye toward winterization, and particularly what can be done to guard against air system freeze-up. Here are some basic tips for operation in the cold weather. Engine Idling Avoid idling the engine for long periods of time. In addition to the fact that most engine manufacturers warn that long idle times are detrimental to engine life, winter idling is a big factor in compressor discharge line freeze-up. Discharge line freeze-ups account for a significant number of compressor failures each year. The discharge line recommendations shown under “Discharge Lines” are important for all vehicles, but are especially so when some periods of extended engine idling can not be avoided. Discharge Lines The discharge line should slope downward from the compressor discharge port without forming water traps, kinks, or restrictions. Cross-overs from one side of the frame rail to the other, if required, should occur as close as possible to the compressor. Dryer Inlet Temperature The dryer inlet air temperature should typically be within the range of no more than 160°F and no less than 45°F above low ambient (surrounding) temperature to prevent freeze-ups. (For example, if low ambient is minus 40°F, the dryer inlet must be above 5°F.) Lower dryer inlet temperatures should be avoided to minimize the risk of freeze-up upstream of the air dryer. Higher temperatures should also be avoided to minimize the risk of heat damage to the air dryer seals and to avoid a loss of drying performance. Compressor Line Size The line size and length is established by the vehicle manufacturer and should not be altered without the vehicle manufacturers approval. As a reference, the line length from the compressor to the air dryer should be less than 16 feet and the minimum line sizes should be as follows: Minimum Length Minimum I.D. Application 6 ft. 1/2 in. Low Compressor Duty Cycle Applications (0-20%) 10 ft. 5/8 in. High Compressor Duty Cycle Applications (20-40%) Line Insulation To guard against freeze-ups in low duty cycle applications, the discharge line can be insulated if it is greater than 9 feet in length. The line can only be insulated back to 9 feet and a maximum of 3 feet. For example, if the line is 10 feet in length, insulate the fitting and the last one foot of the line. If the line is 15 feet, insulate the fitting and the last 3 feet of the line. CATALOG NUMBER 08 www.midwestwheel.com Order NLINE ™ www.midwestwheel.com Order NLINE ™ Made with FlippingBook RkJQdWJsaXNoZXIy MTEyNjY3NA==