Water pressure is a problem in our motorhome. The onboard water pump puts out more water pressure then the city water hookup. When connected to city water we go through an adjustable pressure regulator set at 55-PSI, a dual stage water filter, (paper and carbon block) and then into the coach. Taking a shower is quite slow. I've tried placing the pressure regulator before and after the filter and there is no difference in water pressure. I've also tried the little in-line water filters and a preset 40psi regulator with both types of filters with the same results. I changed the backflow valve in the coach city water inlet when the problem first came up (it was bad), but with no improvement. The only time we get any increase in water pressure is when we remove the filter and then it’s not that much and the onboard pump still puts out more pressure. I've been told that you can augment the water pressure by running the onboard pump when hooked up to city water but that goes against my old teachings to never run the onboard pump when hooked up to city water as you can damage it. What’s your opinion?
Garvin, (Ft. Worth, TX)
Garvin, (Ft. Worth, TX)

Though redundant, it’s doubtful that running the water pump while connected to city water will harm the pump; that’s what its integral check valve is designed for. If you really like that particular filter and can safely set the regulator to a higher output, I’d probably go that route first. Otherwise, I’d look into a freer-flowing filtering media.