Dump Valves?

shields71646 · 03-16-2010, 09:59 PM

I bought a Sandpiper 36.5 earlier this year. It being used I am short on some of the manuals that most likely came with it when it was first purchased.
I am having a little trouble figuring out the dump valves. I believe I have a galley holding tank, a grey water holding tank, and a black water holding tank. Someone please correct me if this is wrong. Looking at the dump valves under the camper I see 2 dump valves on small lines that I assume to be the galley and grey water valves. Where I get lost is where the large line, i'm assuming the black water line, comes out of the tank I have a dump valve right under the tank. I also have another dump valve on the same line before it gets to where the grey water lines y's in. I don't understand the purpose of the 2 dump valves on the same line.
Please tell me if I have it all wrong. Any advice or pics would be appreciated.

**KyDan** · 03-17-2010, 06:31 AM

I don't have your trailer so I can't say for sure but.....
If you have a valve close to the black tank and one close
to the outlet, that's fine.
Keep both closed when you're camping and using the potty.
When it's time to dump open both first. After the black tank
empties open the smaller gray water valves.
This will help flush your dump hose.

The valve close to the black tank helps keep the chunky stuff
from settling in the pipe.
At least that's what it sounds like to me.

**Herk7769** · 03-18-2010, 06:39 AM

Since you bought it used, what it sounds like is the previous owner put an "end of line" dump valve to replace the end of line cap.

This is a common mod. Without the end of line valve, if you have a leaky black water tank shut off valve (or some joker pulled it and put it back in) your first indication of trouble would be when you removed the end cap and got your feet covered in poo.

The valve will allow you to hook up your hose first, THEN open the end of line valve. If there is anything in the line it will run into the hose.

Once the end of line valve is open you can dump the tanks normally.

My guess anyway.

cfsoistman · 03-18-2010, 06:53 AM

Quote:

Originally Posted by herk7769

Since you bought it used, what it sounds like is the previous owner put an "end of line" dump valve to replace the end of line cap.

This is a common mod. Without the end of line valve, if you have a leaky black water tank shut off valve (or some joker pulled it and put it back in) your first indication of trouble would be when you removed the end cap and got your feet covered in poo.

The valve will allow you to hook up your hose first, THEN open the end of line valve. If there is anything in the line it will run into the hose.

Once the end of line valve is open you can dump the tanks normally.

My guess anyway.

I think you're 100% correct. I wish I had the room for the additional valve just to avoid the little surprise in the cap from time to time where the remaining liquids, grey water or worse eventually settles in the cap.

That valve will definitely help avoid that situation.

**KyDan** · 03-18-2010, 07:25 AM

OK, I'll play devils advocate just for the sake of conversation.....
If "some joker" pulls one valve what's to keep him from
pulling the other?

My dump valve occasionally leaks a little --liquid-- into the
small space behind the safety cap. Sometimes it's dry back
there and sometimes there's a cup of liquid.
I can't imagine any "poo" being able to leak past the valve!!
If that happens then we're back to my first question.
If the "poo" got past one valve, whats gonna stop it at valve #2?

Don't get me wrong, I've got nothing against redundant systems.
Just wondering........

bdb2047 · 03-18-2010, 07:38 AM

I have a 2008 Sierra,which I bought new.The valves arrangement sounds the same as yours,the 1 at the black tank you would have to get under trailer to operate.I asked tech when I went over trailer why the 2 valves on black tank,he could not give any reason other than thats how Forrest River does it.I currently leave the 1 open under trailer and use the accessible for dumoing.

cfsoistman · 03-18-2010, 08:14 AM

Quote:

Originally Posted by KyDan

OK, I'll play devils advocate just for the sake of conversation.....
If "some joker" pulls one valve what's to keep him from
pulling the other?

Then the Poo is on him with no cap

. With a cap it's on the poor unfortunate soul opening the cap.

**KyDan** · 03-18-2010, 08:35 AM

OK, I get it.
Don't throw away your cap.
We've been in campgrounds where they wouldn't let you in
unless your cap was in place!

I'm not exactly sure if they were trying to be clean or just
trying to sell caps!

cfsoistman · 03-18-2010, 08:40 AM

Quote:

Originally Posted by KyDan

OK, I get it.
Don't throw away your cap.
We've been in campgrounds where they wouldn't let you in
unless your cap was in place!

I'm not exactly sure if they were trying to be clean or just
trying to sell caps!

Probably both but losing a cap must be one of the most frequent issues. Now that you mentioned it, most of the camp stores we've been in seem to retain a large supply of them.

shields71646 · 03-18-2010, 08:19 PM

Quote:

Originally Posted by bdb2047

I have a 2008 Sierra,which I bought new.The valves arrangement sounds the same as yours,the 1 at the black tank you would have to get under trailer to operate.I asked tech when I went over trailer why the 2 valves on black tank,he could not give any reason other than thats how Forrest River does it.I currently leave the 1 open under trailer and use the accessible for dumoing.

Thanks to everyone for your responses. I have tried a few different things and I believe it is just a double block in case one fails. I also called technical support and they said, thats just the way they are designed. They couldn't come up with a definite reason why they designed them that way.

**Herk7769** · 03-19-2010, 07:01 AM

Remember that the hose is attached FIRST before the end of line valve is opened.

That way no poo at all regardless.

If the end of line valve AND the tank valve leak, you will see it on the ground before you stand near it. (Not very likely at all).

Order of things:

1. Remove end cap on end of line valve (you have one right).
2. Should be no liquid here since any would have drained off when you last dumped.
3. ATTACH sewer hose. (REAL IMPORTANT STEP)
4. Open end of line valve. (any surprises can be heard running into sewer hose)
5. Dump black tank (if required) and close valve
6. Dump gray tank(s) and close valve
7. Close end of line valve AFTER plumbing drains (A clear elbow really helps here)
8. replace end cap.

No poo ever.

Hipshot · 03-19-2010, 08:02 AM

Good check list herk7769. I would add 1 step. BEFORE REMOVING THE CAP VERIFY ALL DUMP VALVES ARE CLOSED. I had a case where someone pulled my black and gray dump valves. I was lucky I noticed them before I removed the cap. I closed them and used a bucket to catch what was in the lines. Could have been a disaster. I like the idea of the end valve, going to look into that.

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