Water Question - Help Please

When hooked to city water you do not use the pump. So leave the pump off.

If you were not hooked to city water, you would then fill your onboard fresh water tank and use the pump.

Do not use the pump when using city water. It can cause issues...

does a destination trailer even come with a water pump?
it's not a typical RV.

Yes - I could hear the pump when we ran the water during the walk-through. I just can't remember what the tech guy said about it. A LOT of info to process!!! Thanks for the help.

As for the holding tanks. The black tank should be allowed to get full before dumping. This will help in the break down and help to stop the build up. You should also rinse the tank out to help keep it clean. The grey tank not so important, I would just make sure you run alot of water so to keep it clean also.

Welcome to the forum! It would be a great idea to post the make and model of what you are describing as a destination trailer. That will help when talking about water, sewer, and what type of tanks your particular unit will have.

NO you do not need the water pump when hooked to "City" water

What you do need is a pressure regulator. Avoid those little brass or plastic cylinder ones get a WATTS or ZURIN 'in line' type 1/2 inch or larger (3/4" may be cheaper) with garden hose adapters.

These have a brass lower housing where you hook up and a bell shaped brass UPPER housing whit a bolt sticking up where the bell would mnount to the carrier. This adjusts the pressure. . Set to 50 PSI.

YOu do need to rebuild them every decade give or take a year or two.

Water supply via connection on side of rig and the on-board pump supply the SAME cold water main line that feeds the toilet, sinks/shower and water heater. Hot out from water heater then feeds sinks/shower

On-board pump has an internal check valve to stop backflow thru pump to fresh water tank when using 'city water' source
'City Water' inlet has a check valve to stop water from flowing out when using on-board pump
Fresh water tank supplies pump only.

Pump pressure switch keeps pump from running if turned ON when connected to 'city water'----provided city water pressure is higher then pump pressure switch.
Pump will come on IF city water pressure drops below pump pressure switch set point.
Only one or other will actual supply the RV with water pressure .....which ever one has highest pressure...so having pump ON while connected to 'city water' will NOT cause any issues

I personally do not even hookup 'city water' ----use fresh water tank and pump exclusively ----just fill/top off tank as needed.
Easier to turn pump switch OFF when leaving rig, just going outside, leaving CG or at night when sleeping VS going out to water source spigot every time I want water off/on.

Fitting broke while on city water ....flooded rig while sleeping.....$6000
IF pump runs (hear it running) then somebody must be using water OR there is a leak. Easier to pickup on pump running then water just flowing

Tank/pump for US!

GENERIC RV Plumbing System----
Not all systems have 'waste tank' sprayers, grey water transfer pump/system, accumulator tanks, toilet sprayers etc.
Like I said GENERIC