A brief video describing how trap pressure unloader valves work, how to operate them, and how to check them for faults or damage if the unloader has lost pressure. It includes how to disconnect and correctly test the unloader.
An unloader valve is used to divert fluid flow into bypass when the trigger is no longer being depressed. The valve can react to a number of things, mainly an increase in pressure or a change in flow. The unloader valve, when combined with the trigger gun, are part of a valve system that works to divert fluid through a bypass and back into the float tank or pump.
The trapped pressure unloader is the most common type of unloader valve, as they are the easiest to use. When the trigger gun is closed, pressure builds up inside the valve until it overcomes the resistance of a spring inside the valve. Fluid is then directed through the bypass port.
