[f5fstop]

I do see a problem with the prime in the unit, but not under normal operation. If primed correctly upon initital install, the check valve should keep the unit filled, since it prevents the fluid from flowing back to the reservoir.
However, the auto mode, automatically squirts the fluid onto the windshield from the Hotshot unit. Unless the hotshot unit also has a pump to draw fluid from the reservoir, it would run out of fluid, till you manually pushed the washer switch to push fluid from the reservoir to the unit.

I will call hotshot today, since their technical support website does not work and ask.

The ones equipped on vehicles from GM are incorporated into the entire washer system.