What keep filling my fresh water tank?

[Hoonanea]

I've been living in my 23D for about 8 months while building a house and through the winter when temperatures get below freezing I've been emptying the tanks and leaving the dump valves open. I emptied the fresh water tank well before winter since I'm connected to city water. But on the first night of freezing temperatures I checked the tank monitor and it showed water in the fresh tank. I turned the release valve on the outside and water came out so I went inside and ran the pump. . . for quite a while. The tank seemed at least half full. Satisfied that it was empty, I buttoned it up again only to find that it had filled about half full the next time we had freezing temperatures a handful of weeks later.

I did not think the fresh water tank filled automatically. I always assumed I had to fill it on my own via the port on the side. Since fresh water is getting in, does this mean I have a failure in my fresh water system somewhere? There are no other noticeable problems. Could the city water pressure be enough to force water the reverse direction through the water pump and back into the tank? I have a good quality brass water pressure gauge/control on the hose and I turn the spigot on only about 1.5 turns giving it a reading right at 45 psi which seems definitely in the reasonable, if not low, range.

Thoughts?

[overlander63]

Probably the check valve on the pump is stuck partly open.

[SteveSueMac]

Overlander63 is right. I was blown away that my FW tank was overflowing when connected to city water....bad check valve on the water pump.

Good luck!

[OTRA15]

Ditto

Lots of posts on bad pump check valves:

https://www.google.com/search?q=Pump...=airforums.com

Your owner’s manual will hopefully tell you where the pump is in your 23D, or check the thread for that model:

https://www.airforums.com/forums/f14...ad-166085.html

While you are at the pump clean out the filter in the water supply line coming from the tank.

Good luck,

Peter

[A W Warn]

Originally Posted by Hoonanea

<<snip>> ran the pump. . . for quite a while. <<snip>>


Thoughts?

Since running the pump did not remove debris, next step>
When you locate the pump, there are four screws that hold the pressure switch onto the pump head. Then there are screws that hold the pump head onto the motor. Remove those screw that hold the head in place. Inside the pump head you will find a rubber diaphragm that has multiple ports (check valve flaps). Look for a small piece of trash, a grain of sand, etc. that is keeping the valve flap from seating properly. Also look for cracks in the rubber. If the pump was not winterized properly the pump head parts can crack if water was frozen.
If it is cracked you will either need to replace the bad part or you might want to spend a few more $ and replace the whole thing while you are at it.
Not a hard job at all!
ps
It's easier to take the pump out of the trailer and onto a bench while repairing it.
ps2
this info is based on my 2888 series pump. your's may be slightly different.

[rmkrum]

All else fails you could consider adding a check valve to the inlet side of the pump between it and the tank as a quick fix.

[Hoonanea]

Thanks to all to replied. I did run the water pump yesterday again to help empty the accumulated water and I left the drain valve outside open. It is not dripping at all this morning like it was yesterday -- so mayhaps the problem is solved for the time being.

I know where the water pump is in my 23D and I can feel the check valve but I cannot see it. Working on it will probably be in the neighborhood of a 10-12 swear-word project despite the mechanics of the task being simple.

Since I'm living in the trailer now while my house is being built, I will live with the small problem, if it returns, until I'm in my house and I have a little more freedom to work on it. It's only a minor annoyance right now.

[Adventure.AS]

Originally Posted by Hoonanea

...

I know where the water pump is in my 23D and I can feel the check valve but I cannot see it. ...

I think that what you can feel is the screen filter between the fresh water tank and the water pump. The check valve is internal to the water pump.

[cazual6]

Originally Posted by overlander63

Probably the check valve on the pump is stuck partly open.

I concur.

When it happened to me, here's what I did. I used the pump for the day or until my tank was emptied hoping the debris from the check valve cleared. It did.

It may happen again, which it did.

What I did to prevent it or having to replace my pump because of it was adding a secondary check valve between tank and pump. Viola!

[OTRA15]

Originally Posted by cazual6

I concur.

When it happened to me, here's what I did. I used the pump for the day or until my tank was emptied hoping the debris from the check valve cleared. It did.
. . .

Good suggestion, which can sometimes also work very quickly, if you turn the pump on and off a bunch of times, within a minute or two, with the city water also turned on and off at the same time. [Might take two to tango.]

The debris in the check valve might just be a few grains of sand/grit which clear out easily. Worth a try once anyway.

BTW always use an inline filter in the hose, both for filling the water tank, and for supplying city water to the trailer's city water connection.

Happy trails,

Peter

[OTRA15]

Originally Posted by Hoonanea

. . .
It is not dripping at all this morning like it was yesterday -- so mayhaps the problem is solved for the time being.
. . .

Still good? Recent helpful suggestions IMO.

Great signature by the way . . .

"Ho'onanea -- to pass the time with peace, ease, and pleasure."

Peter

https://www.youtube.com/watch?v=6a5eWZmNyGg

[T2Airstream]

Originally Posted by Hoonanea

I've been living in my 23D for about 8 months while building a house and through the winter when temperatures get below freezing I've been emptying the tanks and leaving the dump valves open. I emptied the fresh water tank well before winter since I'm connected to city water. But on the first night of freezing temperatures I checked the tank monitor and it showed water in the fresh tank. I turned the release valve on the outside and water came out so I went inside and ran the pump. . . for quite a while. The tank seemed at least half full. Satisfied that it was empty, I buttoned it up again only to find that it had filled about half full the next time we had freezing temperatures a handful of weeks later.

I did not think the fresh water tank filled automatically. I always assumed I had to fill it on my own via the port on the side. Since fresh water is getting in, does this mean I have a failure in my fresh water system somewhere? There are no other noticeable problems. Could the city water pressure be enough to force water the reverse direction through the water pump and back into the tank? I have a good quality brass water pressure gauge/control on the hose and I turn the spigot on only about 1.5 turns giving it a reading right at 45 psi which seems definitely in the reasonable, if not low, range.

Thoughts?

Similar problem with my 1976 AS. Root cause is the check valve that goes between the fresh water supply line and the Fresh Water tank. By design this check value's function to isolate the Fresh Water Holding Tank from the City Water supply line, however due to it's failure to close properly, it allows Fresh Water to not only supply the Fresh Water delivery system, but it allows water to flow directly into the Fresh Water Holding Tank. In my situation the valve isn't fully open, it simply allows water to trickle past.

The bad new here is that this value is part of the copper tube that runs under the floor from the left side of the trailer to the right hand side, absolutely impossible to simple replace. My solution has been to disconnect this copper line in it's entirety and replace it with a flexible line with a new check valve located directly to the City Water feed inside the trailer. Hindsight reveals the manufacture could have likewise placed this value at the Fresh Water supply side instead of adjacent to the Fresh Water Holding Tank ... under the floor. Good luck with resolving your issue and many happy days of Airstreaming.

[guskmg]

To keep water systems clean always use a prefilter were the water inters the trailer, both city and manual fill. That will keep all the debris out of the tank except that left during assembly. I have even eliminated the water hose screen filter at the city inlet. That will increase your overall volume and the filter is redundant with the filter.
guskmg

[OTRA15]

A more recent thread on this FYI:

https://www.airforums.com/forums/f44...nk-218880.html