The unloader valve is an essential component of Vermeer Vacuum Excavator high-pressure water pump systems, serving as a safety mechanism to manage the flow of water. It is a simple yet crucial principle: when the trigger on the digging wand is shut off, the water pressure exceeds a certain threshold, the valve then redirects the water back to the water tank or inlet, preventing damage to the water pump. This intelligent redirection, or bypass, allows the operator full control of the high-pressure water system safely and ensures longevity and reliability for the machine.

• Rated Pressure: 4050psi (280Bar)
• Max Pressure: 4500psi (310Bar)
• Max Flow: 40 L/min
• Max Temp: 90 C
• Inlet: 3/8" Bsp F
• Outlet: 3/8" Bsp F
• Note: No gauge port fitted

If you are unsure which unloader valve you require for your Vac Truck, contact your local RDO Vermeer Dealership to speak to one of our parts specialists.

Vermeer Vacuum Excavators save contractors time, labour, material handling costs, and most of all, reduces surface disruption in areas with improved landscapes and reduce the risks of damaging utilities during the excavation process. Whether it is potholing for a fibre installation or supporting horizontal drilling, Vermeer has a vacuum excavator for your needs. To learn more visit