Sanitizing FW system

[Fitter235]

So I decided to sanitize the fresh water tank and plumbing today. I got a 6 gallon water can and thought I could fill the system through the gravity fill, but it won't take the water in. What am I doing wrong?

[Cate&Rob]

Fitter235
Hi Mark & Cheryl

I am sure that we can help you figure this out. There are a lot of different water systems used across Grand Design products. Could you post a picture of your water panel?
Have you checked the manual that came with your trailer? This is just a guess . . . but, there is often an intake check valve that needs to be turned over before the system will draw in water or sanitizing fluid.

Rob

[tgodrich]

Fitter235
Hi Mark & Cheryl

I am sure that we can help you figure this out. There are a lot of different water systems used across Grand Design products. Could you post a picture of your water panel?
Have you checked the manual that came with your trailer? This is just a guess . . . but, there is often an intake check valve that needs to be turned over before the system will draw in water or sanitizing fluid.

Rob

My system is the Nautilus system on my 2016 303 RLS, and it has the ability to draw water in from an external water source (like my auxiliary tanks I carry for dry camping in the desert) directly into the fresh water tank, utilizing a fresh water hose, and activating the water pump along with setting the valves correctly (I always have to pull out my manual to remember how to set the valves, but it is not difficult). It will pump out 40 gallons in perhaps 15 minutes (whatever the pump capacity is). If you simply had a bucket with your sanitizer in it, you could pump directly from the bucket too. I carry my extra tanks in the bed of my truck., two 40 gallon tanks. On my rig, I do not have a gravity fill for the fresh water tank. At least, I have not found it if I do. Rob may know if I do. :-)

Tony

[Fitter235]

There is a hose off the pump called the winterization hose to pull in antifreeze that does what you are talking about. There is a gravity fill port on the side of the trailer and I should be able to fill the tank through that. I'll try and upload a picture.

[Fitter235]

This is from my manual

[Cate&Rob]

There is a hose off the pump called the winterization hose to pull in antifreeze that does what you are talking about. There is a gravity fill port on the side of the trailer and I should be able to fill the tank through that. I'll try and upload a picture.

The gravity fill port is unique to Imagine. We are going to need an Imagine owner to chime in here.
Guest Jim, can you help here ?

Rob

[Guest]

The gravity fill port is unique to Imagine. We are going to need an Imagine owner to chime in here.
Guest Jim, can you help here ?

Rob

For the gravity fill at the side of my Imagine, there is what looks like a 1 1/4" hose that runs from the fill and directly to the tank. Three issues that I can think of would be a kinked inlet hose at the gravity fill, or a blocked overflow. If the nozzle on the can fits tightly in the gravity fill opening and the overflow is blocked water would stop flowing after a very short period of time. So air must flow out of the tank if water is to flow in. Mdot In = Mdot out.

The third.....is it possible there is a knock out at the inlet of the tank and this was never removed in manufacturing?

Even though some units have the gravity fill at the passthrough rather than the right side of the rig, I believe the gravity fill would still be independent from the city water valve.

For a test by the OP, can the tank be filled from a water hose at the gravity fill, and can water be seen coming from the overflow when the tank is full?

Jim

[Yoda]

Do you have a faucet open when trying to pull from your bucket? Also some folks say to flip the inlet screen in the city hose port to hold the check valve open. If you do this be sure to flip it back for normal use.
Hope this helps

[Fitter235]

Some good suggestions that I will try in a few hours. Thanks

[ShawnErtha]

Still should be able to add through the gravity fill port if needed. I'm wondering if there is a kinked line.

[Fitter235]

Well, after trying several things and not having any luck, I was throwing in the towel and was going schedule an appointment at the dealer to look at it. I decided to try one more thing and stuck my garden hose in the fill port. It took the water just fine. Then I tried pouring water in with my 6 gallon jug and it still would not work. I think there is a spring loaded check valve in the fill hose. The garden hose has enough pressure to overcome it, but just pouring in water won't work.

[Fitter235]

No, does not have a screen. just a hole.

[howson]

Fitter235 -- a check valve on a gravity fill port? If so I'd think that trailer was built incorrectly. Why would GD put a check valve on a gravity fed water line? I could be wrong and the valve is bad (too strong). The WATER SUPPLY PLAN drawing I have access to (it's an older drawing last updated 3/2017) does not show a check valve on the gravity feed line.

Guest's suggestions in post 7 of a kinked hose or blocked vent sounds more likely. The pressure from the hose is overcoming the kink where the free-flowing water can't.

An easy test to check the tank's vent line--open the drain on the bottom of the water tank. (If you have a lot of water it will all be lost!) Now try and fill the tank using the gravity fill with your 6 gallon jug. If water flows freely through the gravity fill line, through the tank and out the bottom of the drain line, the problem is associated with the tank vent. If the tank still won't take water, the gravity fill line is pinched somewhere.

Of note, the OEM fill port part is here: https://www.granddesignrv.com/owner-...s/detail/30304 I do not see a vent on the part like the vent seen on the aftermarket version (Valterra on Amazon: https://www.amazon.com/Valterra-BLAC.../dp/B0735HHB84). The pic below shows the vent I'm referencing that I don't see on the OEM version (and why I think the vent on the tank in your Imagine could be the issue):



-Howard

P.S. Cate&Rob -- I'm definitely straying into a subject that for me is deep water (pun intended), so please double-check the drawing I referenced and validate (or debunk) the test/info above. Thanks!

[Guest]

Howard,

The vent as shown by your arrow in the pic is not connected on my Imagine. Under the rig there is a drain and an overflow. You are correct, the overflow is the vent on my Imagine.

There is no check valve.

Jim

[ckreef]

This spring I sanitized my 2020 2600rb using a funnel and pouring the bleach mixture in the gravity feed port. I too doubt there is a check valve in there. Page 97 of the Imagine owners manual says "Pour the chlorine/water solution into the gravity water fill inlet." That port is meant to be a gravity feed port

Looking in mine with a flashlight I can see the white hose go straight back for a few inches then gradually slope downward. Look in your port you might be able to spot the kink if there is one near the port.


Also in the upper left corner of gravity feed port there is a small round "screen". I'm guessing that is an air vent for the fresh water tank.