Water fill issue

[chrizg]

I have a 2009 Heartland that has the water fill issue. During these years of production they didn't run the vent tube very good so it sometimes fills with water if I overfill the fresh water tank. Sometimes raising the front of the camper will let the water out of the vent tube or forcing some air down the tube.

After dewinterizing this year I was sanitizing the fresh tank and I was filling and draining it a couple times. When running the water to flush the lines I dumped the grey tanks twice during the sanitizing process and when I would pull the release valves the vent tube would instantly start breathing like it does when I force air down it when it has water in it and the fresh water won't fill

Question is.. Why would pulling the grey tank valves cause the fresh water tube to open up and breath like that. How would those two be connected ?

[ctpres]

If tanks are stacked - emptying one tank could relieve pressure on the other allowing it to expand and suck air?

[FlatBroke]

I carried two foot piece of heater hose with our Bighorn. I just put the end of the hose up to the vent and blew it out. Worked like a charm.

[skipnchar]

eHoefler wrote:
The fresh water system IS NOT and SHOULD NOT be connected to any sewer vent of any kind!!!!

X2 and I would add that the FW tank should also not be pressurized under any circumstances. Some years back there were a few brands that used a pressurized FW tank instead of an electric pump but haven't seen one of those in 20 years or so.

[beemerphile1]

Only way it would happen is if the vents are tied together and that is a violation of every code on the books.

[eHoefler]

The fresh water system IS NOT and SHOULD NOT be connected to any sewer vent of any kind!!!!

[GENECOP]

It is a complete system, in other words the RV plumbing system is closed with vents sometimes tied directly to the fresh water tank, if not direct connected in some way by a branch....hard to explain but if you Google RV plumbing systems (IMAGES) you will see....