Fresh tank overfilling and leaking into camper

[68Birdman]

Camping this past weekend connected to city water and the fresh tank overfilled and leaked into the camper. I read posts here and learned I need a new check valve on my water pump.

Why it is leaking inside? It doesn't leak when I manually fill the tank with a hose. Possibly the overflow vent?

Thanks!

[Kimber45]

you dont need a new check valve. Read the other million threads on the subject. Turn off the city water. Disconnect. Turn on the pump. Turn on and off a sink cycleing the pump on and off and 9/10 times it will fix it self. If it wont. Then you need a new pump.

It should be leaking out the over flow tube. If that overflow tube cant keep up with the preassure from filling the tank then i could see leaks inside or the tank blowing up.

[Life Without Whine]

we cheat - pull the plug off the fresh water tank each time we land & it doesn't allow for some sort of pressure to back up that messes with the pump so we haven't changed it yet! So far, so good

[Gmoney67]

You dont need new pump just put in check valve be done.

[dmayo32]

While I was able to stop mine from leaking I added an external manual valve just in case to stop the flow back to the pump when connected to an outside water source. Luckily mine is easily accessible to turn it on or off as needed.

[Larry-NC]

A less common case of overfilling the fresh water tank can occur of your trailer has a Shower Miser system.

This system is intended to be used only if you are boondocking--living off the fresh water tank, with no city water connection. When boondocking without a Shower Miser, you would run the shower until it's hot before getting in. This moves precious, perfectly clean water from the fresh water tank through the water heater and shower and on to the gray tank. This pushes two limits: depleting the fresh water and filling the gray water tank. With the Shower Miser, water moves from the fresh tank, through the water heater and back to the fresh water tank.

If someone misunderstood how the system was supposed to be used and made a practice of using the Shower Miser while connected to city water, the fresh water tank would eventually fill and overflow, even though the check valve was in perfect order.

Does your camper have a Shower Miser? Does everyone know when it's supposed to be used?

[RStormC]

Go to the local plumbing supply store and buy a check valve. Install it on the intake side of your water pump. Solved my problem immediately. I had to buy a union because both ends of the check valve were female fittings.

[Larry-NC]

Originally Posted by RStormC

Go to the local plumbing supply store and buy a check valve. Install it on the intake side of your water pump. Solved my problem immediately. I had to buy a union because both ends of the check valve were female fittings.

Also available at Lowes and Home Depot.

Actually, you can put the check valve on the input OR output side of the water pump, whichever is the most convenient. Just be sure that in either case the arrow on the valve points AWAY from the tank and toward the trailer fixtures.

[5picker]

One more "quick fix" for those with a winterization/bypass valve near the pump... turn the winterizing valve so it cuts off the supply from the fresh tank and then screw a $0.50 garden hose shut-off on the outside winterizing port. (or a pipe cap if your hose doesn't go to the outside)

While this won't "fix" your check valve issue, it will buy you time to continue camping without the fear of your fresh tank overflowing and making a mess.

[DougW]

Originally Posted by Larry-NC

Also available at Lowes and Home Depot.

Actually, you can put the check valve on the input OR output side of the water pump, whichever is the most convenient. Just be sure that in either case the arrow on the valve points AWAY from the tank and toward the trailer fixtures.

If you put the check valve on the output side of the water pump, when you are using the pump the pressure in the water line will bleed back through the water pump and the pressure sensor will turn the pump on until the pressure comes back up which be a fraction of a second. The pump will then stop again until the pressure bleeds off again. Putting the check valve between the he pump and the water tank works much better.

[68Birdman]

Thanks everyone for your comments. I haven't had an opportunity to try your suggestions as work has kept me busy. I don't have a shower miser but I might have to look at one. As soon as I'm able I'll try some of the tricks here and let you know how it turned out. I also have a Camco check valve ordered for the inlet side of the pump. I'll have to re-orient the pump as the winterizing port I installed puts the inlet 90 too close to the cabinetry. I also plan on blowing some air through the over flow hose just to make sure it's clear. I really want to understand why water was leaking into the camper. Thanks again!

[RStormC]

Originally Posted by 68Birdman

Thanks everyone for your comments. I haven't had an opportunity to try your suggestions as work has kept me busy. I don't have a shower miser but I might have to look at one. As soon as I'm able I'll try some of the tricks here and let you know how it turned out. I also have a Camco check valve ordered for the inlet side of the pump. I'll have to re-orient the pump as the winterizing port I installed puts the inlet 90 too close to the cabinetry. I also plan on blowing some air through the over flow hose just to make sure it's clear. I really want to understand why water was leaking into the camper. Thanks again!

On my camper the overflow was the same as the fill tube. I believe that it overflowed and followed the tube back down to a contact point, and then into the trailer. In any event, I awoke to a completely soaked mattress.