Alde gushing water from drain underneath

Babs

Hello Tabbers;

The discovery of gushing water out the drain underneath the tab happened when I turned on the Alde for some hot water.  Then I opened the door just in time to see a huge puddle on the ground from the Alde tank.  After changing out the regulator, checking for internal flooding, and testing the outside spigot, apparently water flowing directly from the spigot runs directly through the Alde and out the drain under the tab.  Presently there doesn’t appear to have any water in the tank.  What could have happened?  Plus what steps are next please?  Any help is greatly appreciated!

pthomas745

What year and model is your trailer? 

Welcome to the:Famous Yellow Flapper Valve.  The Yellow Valve is one of the drains for the Alde tank.  It also works as a pressure relief valve for the trailer plumbing.  If you are on city water, and you are not using a pressure regulator on the hose, your Alde yellow valve will open to "relieve" the overpressure.

Most of the trailers have the Yellow Valve down next to the Alde under the driver's side bench.  (If you have a 400, you may have 2).  So, open up the area under the bench where the Alde is, and look for the Famous Yellow Flapper Valve.

You might also have an open "low point drain valve".  These might be in different spots in the trailer, so let us know the year and model.

PS: don't feel bad, happens to everyone. Find and use a water pressure regulator.

PSS: In the newer trailers with the Nautilus, this valve is a bit "out of sight, out of mind". 

This photo is a 2021 320.  The Yellow Valve here is "horizontal", and closed.

PSSS: I see you had a regulator: sometimes, the Yellow Valve gets forgotten when buttoning up the trailer after winterizing, etc.  It may have just been left open.  So, close whatever valve that may be open, and test your regulator again.

This is a picture from the Alde manual.

Babs

Hello and WOW!  Your instructions worked!  Niagara Falls is now turned off.  In a calm panic, I was wondering the replacement cost for a 3020 unit.  Bless you!!!

pthomas745

Good! When you look under the trailer, there are several little "spouts" down there. These are year and model dependent, so saying what year and model trailer you have really helps.  The Alde Yellow Valve drain(s) are directly below the actual valve in the Alde area, so it is usually easy to tell what drain might be open.

krsmes

In addition to the "If you are on city water, and you are not using a pressure regulator" issue, the valve, specifically the one on the hot water line, can also open and release all the water if the hot water builds up too much pressure in the system.   I don't know if there are other reasons or why this would happen but we had it happen while boondocking/dry camping (and lost all our water).

"In a calm panic, I was wondering the replacement cost for a 3020 unit" -- as we are in the middle of this now it runs about $3k installed just for the boiler unit.

Babs

Hello, 

I am sorry for the delay in responding—thank you for your comments!  Replacing the boiler unit is a challenge; did you opt for an Alde or something else?  How’s it working now? Lastly, do you mind describing what caused the boiler to break?  

pthomas745

There have been some boiler issues: bad welds, or just "failures".  Its sad that this has happened, but it is very rare.  It is not possible to say why this happens except for manufacturing issues.  The Yellow Flapper pressure relief is probably more related to the protection of the various plumbing fittings through out the trailer, not necessarily the Alde tank.

Babs

Thank you again!

krsmes

@Babs I wish knew why it failed. The assumption is some sort of corrosion that affected the internals. Here’s the story https://tab-rv.vanillacommunity.com/discussion/17138/alde-unit-seeping-all-its-antifreeze-onto-the-floor