Abstract: In a liquid pumping apparatus, such as a pressure washer, the outlet is selectively connectable to one of two different conduits. The pump for the apparatus is an electric pump and is connected with an electric switch. A manually operable button operates the switch between its pump activated and pump inactivated positions. A spring is selectively urged against the switch lever to bias the switch lever to the pump inactivated position through a pivoting plate. The pivoting plate is pivoted toward or causes the spring to bias the switch lever by a tang extending from one of the conduits for transmitting liquid from the apparatus outlet. Operation of the pump then requires continuous pushing on the switch operating button by the operator. With a different conduit in place and/or no contact of the tang with the spring contacting plate, the spring relaxes away from abutting the switch lever.