Boon Docking with fresh water tank and pump

[SET1949]

I am a 2 yr owner of a Freedom Express 192 RBS but a newbie to boon docking. I recently camped for the 2nd time without water and power hook-up. Before I set up, I filled my Fresh water tank at the campground potable water outlet. I did not bypass my water heater and turned the water pump on. I could hear the hot water heater filling so I know the pump was working. When I opened the kitchen water faucet, it spit and sputtered air which was expected. What was not expected was for the entire 3 days camping, i never got good pressure and always had spitting of air. The faucet in the bath was worse. No pressure at all, just a trickle of water.
Did I do something incorrectly, or do I need to have a technician look at my water pump and lines?
Any experienced comments are welcomed.

[MtBiker]

Be sure all your valves are in the correct orientation for use. Check that the screw cap on the filter just before the pump is tight and is not cracked. If it is lose it will suck air. If the winterization tube for adding antifreeze is not capped it will also stuck air. If something cracked during a freeze you will suck air.

[HaroldPE]

I find it works better for me if I use city water connection at home to purge the lines of air.

I also release any air in the water heater after filling using the relief valve.

Once I disinfect and use the water tank first time in spring, I leave water in the system all summer.