Dultmeier Sales will be closed Thursday, November 25th and Friday, November 26th in observance of Thanksgiving

Dultmeier Sales will be closed Friday, December 24th.
Normal operations will resume Monday, December 27th. We wish you and your family a very Merry Christmas!

Dultmeier Sales will be closed Friday, December 31st in observance of
New Year's Day

Dultmeier Sales will be closed Monday, July 5th in observance of Independence Day.
Normal operations will resume Tuesday, July 6th. We wish you a happy 4th of July!!

We are experiencing some technical difficulties on dultmeier.com and apologize for any inconvenience.
If you are running into issues, please phone your order in to 1-888-677-5054

Customer Pickup Orders: to help reduce exposure for our customers and our employees, if you are placing an order for in-store pickup please call in your order ahead of time or place your order online and pre-pay with a credit card. Be sure to let us know when you plan to arrive. We will have your merchandise ready for you and will greet you outside our facility. Thank you for your help!

Testing Unloader Valves | Video

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.