Multi-switch pump assembly

A method for switching fluid flow through a pump assembly, the method comprising

• rotating a motor shaft;
• housing in the pump assembly a first pump stage having a first impeller connected to and rotated by the motor shaft for pumping fluid through the first pump stage and a second pump stage having a second impeller connected to and rotated by the motor shaft for pumping fluid through the second pump stage;
• moving a valve assembly into a first switched position to fluidically connect a first fluid inlet and a first fluid source to the first pump stage, the first pump stage having a first and a second fluid outlet, the first switched position fluidically connecting the first fluid outlet to the first pump stage, wherein the first pump stage pumps fluid from the first fluid source to the first fluid outlet;
• fluidically connecting a mixing chamber housed in the pump assembly between the first pump stage and isolated from the first pump stage to the second pump stage, the mixing chamber fluidically connected to a second fluid inlet and to a second fluid source, the second pump stage having third and fourth fluid outlets and the first switched position fluidically connecting the third fluid outlet to the second pump stage, wherein the second pump stage pumps fluid from the second fluid source to the third fluid outlet;
• moving the valve assembly into a second switched position fluidically disconnecting the second pump stage from the third fluid outlet and fluidically connecting the second pump stage to the fourth fluid outlet, wherein the fluid from the second fluid source is pumped to the fourth fluid outlet;
• moving the valve assembly into a third switched position to fluidically connect the first fluid inlet and the first fluid source to the second fluid outlet and to fluidically disconnect the first pump stage from the first fluid outlet, the first pump stage pumping fluid from the first fluid source to the mixing chamber where it is mixed with the fluid from the second fluid inlet and the second fluid source and the valve assembly in the third switched position fluidically connects the mixing chamber to the second pump stage and the third fluid outlet disconnecting the second pump stage from the fourth fluid outlet, wherein the second pump stage accelerates and boosts the mixed fluid to the third fluid outlet;
• and
• moving the valve assembly into a fourth position fluidically disconnecting the second pump stage from the third fluid outlet and fluidically connecting the second pump stage to the fourth fluid outlet, wherein the second pump stage accelerates and boosts the mixed fluid to the fourth fluid outlet.