My current setup uses an aluminum 7-gallon tank which is on a quick disconnect fitting. It has a bleeder valve at the top so I can remove the tank from the bed, invert it, and bleed out any water which has built-up in the tank. I plan to do this about once every few months but I am not that worried about it since the tank is aluminum.
My main concern is water which builds up in the air lines, fittings, valves, horns, and compressors. I don’t want those to rust, corrode, or clog. My compressors and tank are in the truck bed, which has a hard cover so no outside exposure to the elements, with horns and valves under the truck. I am worried that some water will build up at several points after the tank. If this is a possibility then it would seem best to place the water trap on the air intake lines between the dual 400c compressors and the air filters? This would prevent moisture from getting in to the system to start with so everything would be protected, but will it allow enough air flow to feed the compressors? Another option would be to place a filter in the main line before the valves just as the line drops under the truck, but would this restrict airflow to the horns?
Basically I want to add complete water protection but not at the risk of reducing airflow. If the components won’t be damaged by a little water then I can just drain my tank periodically. Any advice from the experts on the best water trap method and location for my system? Details of the system are in my signature with a link to the complete system diagram.