Water problem? Help

OK I called our dealer and and send them a picture that I took of it and they told me that I might have a valve turned that is suppose to fill the fresh water tank when the city water hook up is hooked up. The valve is not labeled and when we took delivery of the camper the gentleman told me that valve was to turn the flush for the black water tank. It is not labled but they told me to try that so I will let you know everyone know. I hope that works!

AS suggested.....two ways for fresh water tank to get filled when connected to 'city water'

IF you have a water panel where hose connects than check the valving...fill tank valve open.

Otherwise the on-board pump internal check valve is letting water run thru pump back into tank
The internal check valve can get build up on it from hard water or debris from tank holding it open.
Running the pump can clean out the debris (and lower the fresh water tank).
Cleaning the check valve is easy....just remove pump head and clean diaphragms
OR replace with new.

Sounds like you have set the valve for "tank fill". Check in your utility cabinet for a quarter turn handle, it should be marked for tank fill in one position and city water (or something similar)in the other. Post back so others can learn from your experience.

There should be a check valve at the water pump to prevent this, its probably got some trash in it, turn off city water and use the pump for a bit then switch back, hopefiully that will cure it.