[uwe]

Hi Dan,

I had the exact same problem like you when hooked to city water. I found the following problems:
The water drip when using the pump was caused by a defective one way valve somewhere in the system. I purchased a new hose connection and screwed it on the city water input pipe, and it took care of the problem. The hose connection has a one way valve in it, plus a cap so you can close it off while travelling. I found it at Camping world.
The other situation was a overpressure valve doing it's job. I am referring ot the drip behind the rear wheel. The trailer has a valve with a hose attached to it next to the water heater. If the city water pressure gets too high, then the relief valve will let off excessive pressure, resulting in a drip behind the left rear wheel. It is doing it's job...... So, I solved this by using an outside pressure regulator right at the faucet, before the hose that goes to the trailer. This way the hose is protected as well.
Ideally one should remove and clean the pressure regulator and relief valve on an older trailer. I will do this when camping season is over. One or the other items will probably need replacing.