Modification to fill fresh water tank?

[Bjwinspect]

Instead of using the exterior opening to fill the water tank has anyone made it so that it could be filled when the ?city? water supply is connected?    I am thinking about putting a ?T? into the water piping on the opposite side from the pump from the tank, connecting this into the overflow piping at the top of the tank.  Using a inline valve to fill my tank when I am connected to ?city?.  I realize some coaches probably already have a similar setup.  Any problems doing this that I am not aware of?

On another note, I just get the EEZ RV TPMS.  Easy to set up, One feature I did not realize it has it the ability to just show the Toad on the display.  This makes it very useful in my daily driver when I am not using the motorhome

 

[Chakara]

The things that pop in my mind are:

1) overpressure - make sure that tank can breath while filling it.
2) overflowing - maybe some type of float cutoff?

-Kyle

 

[HueyPilotVN]

My Country Coach has the type system that you are considering.

The issues of both overpressure and overflowing are taken care of in my system by the overflow drain that protects the fresh water tank by allowing the water to simply drain if it gets completely full.

Edit:  I am guessing that you already have an overflow to let you know when to stop filling the fresh water tank.

Tomorrow I will see if I can remove the cover in the plumbing compartment and see if I can take pictures of the plumbing system.

I also have some very detailed drawings in my documentation and I will see what they have on the plumbing layout.

Should be fairly straight forward.  Access might be the biggest issue.

 

[Bjwinspect]

It would still be able to vent though the fill opening, the cover over the opening can?t be sealing too tight, I think this should also serve as a overflow, but if it did get to where it was overflowing out of the fill opening, I would just drain a bit off to get to a practical level.

 

[Lou Schneider]

Instead of taking the fill valve's outlet to the vent tube,  backfired  the tank outlet that supplies water to the water pump so the tank vent stays intact.  All you need are tee fittings at the pump's inlet and outlet with an on/off valve in the middle.

Leave the valve off for normal operation.  When you want to fill the tank, turn off the pump and turn on the valve while you're connected to city water to send water into the tank.

 

[HueyPilotVN]

Instead of taking the fill valve's outlet to the vent tube,  backfired  the tank outlet that supplies water to the water pump so the tank vent stays intact.  All you need are tee fittings at the pump's inlet and outlet with an on/off valve in the middle.

Leave the valve off for normal operation.  When you want to fill the tank, turn off the pump and turn on the valve while you're connected to city water to send water into the tank.

I will look behind the panel tomorrow, but I am fairly certain that my valve to divert water to the fresh water tank is located on the inlet side of the pump.

I have no gravity fill port.  I do however have a seperate inlet port that has a valve and acts as a suction port for filling the fresh water tank from a source such as a tank or even a lake/stream type source using the onboard water pump.

Now I am not an early rider, but I will do it tomorrow.

 

[Old_Crow]

;My coach came set up like this and the PO disabled it.  When I had the coach re-plumbed, I had the guy put it back. 
Basically it's 2 tee's in the inlet and outlet lines for the pump, with a short piece of water line and a valve connecting them.
With the coach hooked up to city water, this is how it works:

Valve closed, normal operation either of the pump or city water. 
Valve open, city water flows into on-board tank, bypassing the pump. 

When the tank is full it overflows out the vent tube in the gravity fill port.

 

[John From Detroit]

Many RV's already have that feature.. Mine does.

The system on my (And most so equipped) RV's consists of a 3-way valve (QUick Fill) that sends water either into the house system or into the fill line. an additional line to the tank.

I would suggest you put a spigot in the wet bay near the fresh water fill (Gravity fill) and use a short hose.

 

[HueyPilotVN]

Here are two pictures of the wet bay.

I did not remove the panel as it looked like more of a task than I originally thought.

The port in the upper right is for siphoning from an outside source or antifreeze for winterizing, (which I never do).

The second hose that goes to the tank flush I added because I got tired of switching hoses to rinse.  It has two shut off valves and a back flow preventer to insure that it does not contaminate the hose or fresh water tank.

 

[Bjwinspect]

Thanks.. that gave me some ideas.. time to get some pipe fittings

 

[blw2]

I just made up one in mine a few weeks ago.  Easy enough.  Have been meaning to do this for a long time now.  Haven't had it long enough to report performance or problems, but it's basic.

My tank and water pump is behind some blind kitchen cabinet panels.  The hardest part was modifying the panel with friction clips so that I didn't have to use a tool to remove the screws.

Mine is pex, so I used the sharkbite type fittings.  Push on and easy.

Found a place downstream from the pump that was easy to get to for the tee.
At the port they had installed for winterization and antifreeze (a threaded connection with threaded plug), between the tank and pump, I replaced it with a tee....
One leg loops up to a ball valve and back to that first tee on the discharge side
the other leg of the suction side tee is now a valve with a piece of tubing that I can use to drop into a jug of antifreeze if ever needed...without tools

My tank vent is a rather small diameter vinyl tube, so I plan on uncapping the gravity fill whenever I'm using this system.

It would have been nice to do up a panel mounted valve in a bay someplace, but didn't make easy sense in my rig

 

[Bjwinspect]

I just finished.. what I ended up doing was putting  a T in the water line after the pump and adding a hose faucet.    I can  just use a short hose for the  gravity fill if needed      The extra hose  connection at the rear of the coach may come in handy.   

ALSO, I got a female to female hose adapter that I can put on the rear hose faucet giving an additional city water connection on the opposite side from my factory connection location.

 

[Frank B]

Instead of taking the fill valve's outlet to the vent tube,  backfired  the tank outlet that supplies water to the water pump so the tank vent stays intact.  All you need are tee fittings at the pump's inlet and outlet with an on/off valve in the middle.

Leave the valve off for normal operation.  When you want to fill the tank, turn off the pump and turn on the valve while you're connected to city water to send water into the tank.

Yep, works great! I did that a few years ago, but used a valve with a DC solenoid control on it. I just put an electrical switch beside the fresh water fill on the unit. Now I just open the water fill door, and flip the switch. Unscrew the cap in case of overflow, and just stay there until the water pours out.  Saves a lot of fooling around.