Single impeller shower pumps are a great solution for boosting the pressure of one of you water supplies to an outlet. These particular single impeller pumps have a negative head which means they’re designed for installation where the outlet is in a higher position that the cold water storage tank. The bar refers to the pressure or boost provided by the pump, anything below 2.0 bar will be a low to medium increase in pressure while 2.0 bar and above would be a more powerful increase.
