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Camper Mod Contest Entries

Fill Your Water Tank While Hooked Up

Welcome to the second entry in April’s Medium Mod Contest.  One Medium Mod will be published in every Email Alert in April.  At the end of the month we’ll hold a reader vote to determine April’s winner.  Click here for information about the 2021 Mod Contest, including how to enter.

Water tank fill while hooked up

Dominik Knapp, Newark, California
Fill Your Water Tank While Hooked Up
2016 Ford F350
2017 Lance 1172

We were a bit annoyed by the tank filling process.

First, I don’t like having to drag the fill hose over to the other side and babysitting so that the filler funnel won’t slip out of the filler port. It is not very convenient, especially at campgrounds with hookups. There are times when we have to fill the tanks for a few days of upcoming boondocking or camping with no hookups like at state parks.

Second, there are also extended boondocking occasions when we refill our tank with portable 5 or 10-gallon containers that we carry in our truck. Our filler port is very high on the camper and it is quite annoying to have to hold up the heavy containers until they are emptied out by gravity spilling a ton of water in the process.

Fill Your Water Tank While Hooked Up Winterization Valve

I reviewed the piping at my water pump and figured I could use my city water hookup during campground visits to fill the tank. As a byproduct of this change I can also use the winterization valve and pickup hose to pump water from external canisters into the tank of the camper. That eliminates both issues with one change.

Fill Your Water Tank While Hooked Up Schematics

In order to use the city water hookup to fill the tank, one needs to create a path for the water from the cold water line (after the pump) to the tank (vent line, or in this case, pump pickup line).

This was relatively simple with the addition of a couple different fittings that are rated for potable water and a maximum of 125 PSI. I happen to use FLAIR-IT fittings, but other systems would probably work just as good (PEX, Shark bite, etc).

Fill Your Water Tank While Hooked Up Tankfill

I used a couple different adapters to T-off at the cold water line and at the pump pickup to splice in the new shutoff valve. Everything in my camper is half-inch PEX or NPT.

I now have a valve that I can turn to start filling the tank while hooked up to city water.
When it’s not hooked up, I can use this valve and winterization valve to pump water straight into the camper’s tank.

Fill Your Water Tank While Hooked Up

It has worked awesome. There is no more unhooking of hoses and no more lifting of heavy water jugs. I couldn’t be happier with how this turned out. A positive by product is that you are hooked up to your RV’s water filter while filling the tank. It is actually a very simple mod that makes filling your tanks much easier.

The parts used in my system are:

FLAIR-IT 1/2-inch plastic PEX Male Pipe Thread x BSP Female Swivel x Male Pipe Thread Stacking Manifold Tee # 308745696
FLAIR-IT 1/2-inch Plastic PEX Compression Ball Valve # 308745574
FLAIR-IT 1/2-inch Plastic PEX Compression x 1/2 in. Male Pipe Thread x 1/2 in. Compression Tee # 308745688

This may change depending on the connections available in your camper.

It took me 30 minutes to install and cost me $20.  In my opinion, the skill level of this modification is easy to medium.

Disclaimer: The modifications above are submitted by Truck Camper Magazine readers. It is your responsibility to make sure that any do-it-yourself modification project you undertake is safe, effective, and legal for your situation.

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If you’d like to enter a modification you’ve done on your truck camper, click here. You can enter as many mods as you want, at any time.  Good luck mod makers!

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