I've had this question come up several times: Are there any inline variable-speed pumps for maintaining water pressure in residential plumbing?
The only systems I know of seem a little kludgy because they require a pump to provide all pressure, taking the municipal pressure out of the equation. I.e., they either:
- Put a pressure reducer before a single-speed pump, so that the pump plus reduced pressure doesn't exceed ~70psi under low-demand flow conditions.
- Put a tank before the pump, and have the pump run out of the tank.
Given where the state-of-the-art is in high-efficiency, variable-speed motors I just wanted to make sure I wasn't missing something that could be plumbed in-line to supplement municipal pressure as demand varies.