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dznf0g · 04-22-2013, 08:04 AM

I distinctly remember this discussion relative to a particular plumbing problem in another thread some time ago. Don't remember enough to find it. It was verified that some more recent floorplans do indeed dump bath sink into the gray tank. It prompted me to experiment with mine and verify that mine doesn't.

This is not necessarily a bad thing for 2 reasons.

We seem to always run out of gray capacity before black.

And,

The extra liquid from the bath sink ensures a good proportion of solids vs. liquid for a good black tank drain.

Gene · 04-22-2013, 09:24 AM

The way to check whether the bathroom sink is plumbed into the black tank is to shut of the valve that supplies water to the toilet, open the toilet valve that lets water out of the toilet (different valve—the shut off valve should be behind the toilet), and turn on the water in the sink. If you hear water flowing into the tank, then the sink drain is plumbed into the black tank. I don't know if you could see it with a flashlight. You could empty the black tank, turn on the water in the sink, go outside and watch whether water comes out of the black tank drain if you have a transparent sewer connection.

I tried the former method and it appeared the sink wasn't plumbed into the black tank.

For the past several years, some Forum members have said their bathroom sink is plumbed into the black tank and others have said theirs isn't. What models are and aren't—I don't know. Most have said it makes sense to have the bathroom sink drain into the black tank for the reasons stated by Rich above. Another Airstream mystery.

When bookdocking, we use a dish pan in the kitchen sink when washing dishes and dump it into the black tank to save space in the grey tank.

Gene

polarlyse · 04-22-2013, 09:48 AM

OOOohhhhh, I try to learn something new every day. Sometimes it works, sometimes not. First I've heard of it and it does make some sense. I did know that some models have only 1 waste tank and then it's a no brainer. But didn't know otherwise. I'll have to look deeper into mine just to know. I wouldn't want my plumbing doing something I didn't know about. We also do the dishpan trick.

Thanks all. See ya on the road sometime.

dkottum · 04-22-2013, 10:35 AM

My two Airstreams, 2012 FC 25 Front Dinette and 2007 Safari 20, both drain bath sinks into the black tank. Fill the bath sink with water, turn off water supply, push the toilet flush and hold open, pull the sink drain and look/listen for the water draining into the black tank.

doug k

KJRitchie · 05-23-2013, 12:30 PM

Quote:

Originally Posted by KJRitchie

Here is my elbow. It was impossible to find a single piece male 1/2" elbow so the Home Depot gal showed me a PVC elbow with female 1/2" and then took me to the sprinkler section for two male extensions. I used a little plumbers tape and screwed in the male fittings and then installed it on the black flush line. I did'nt have a water hook up so I connected a hose from the exterior hose fitting and ran it into the black flush fitting, turned on the water pump and verified no leaks. Then I pushed the hoses under the wardrobe frame and the elbow is now behind the shower.

I bought a 2 1/2 gal shop vac for the Airstream and vacuumed out all the debris. Everything felt dry. I also purchased a small bag of 2" pink insulation and stuffed it along the aluminum wall inside. Hopefully this will be the end of this.

Kelvin

This last weekend was the first opportunity to test out the replacement elbow fitting under high pressure. We had a full hook up site so when it was time to dump I hooked up my black flush hose and turned on the water then went into the closet area and reached in the access hole and followed the pipe up to the elbow and found........ some water leaking. Darn. Not much of a leak but like a dripping tap. Think its coming from the the female fittings. I'll have to check it out this weekend along with the shower leak repair part deux.

Kelvin

KJRitchie · 06-03-2013, 11:26 AM

Found a better elbow at an RV dealer parts and my black flush doesn't leak anymore. Its a one piece elbow, gray, with male ends.

Kelvin

Bellah · 07-15-2013, 10:25 PM

I would also like an answer to this question.
I just noticed a small water leak under my sink which is just opposite the exterior
black tank flush inlet.
Mine also says to be sure to have the valve open prior to using. However, I ignored this and used it to fill my tank for extra flushing. I'm wondering if this added too much pressure and caused a leak?
When I tried to look up under there, something fell into the wheel well. I think it was some sort of "cap" on top of a vertical vent? the top has a spring loaded something?
I can't be more descriptive because I can't see it.

Any body know something about this?

p.s. It looks like the cabinet would have to be taken out to get to the plumbing?
I can't see a way to get it out. Help?

TBRich · 07-15-2013, 11:27 PM

Not having the drain valve open will not add any pressure to the flushing mechanism to cause a leak...but you need to be care not to let the black tank overflow. We use our flush the same way you do, adding water to the black tank to create more of an out-flow force when dumped. If we have time and opportunity (not all dump stations are set up with a threadable water source) we close and repeat until the output is clear.

If the leak is coming from the inside connection of the flush inlet you may need to hand-tighten the interior coupling ...we had to do that and I check it periodically to make sure it has not worked itself loose. It's not easy to get to, though, as you know.

I can't tell you what the "cap" is that you are referring to. Sorry...

dznf0g · 07-16-2013, 07:21 AM

Quote:

Originally Posted by BlueBelle

I would also like an answer to this question.
I just noticed a small water leak under my sink which is just opposite the exterior
black tank flush inlet.
Mine also says to be sure to have the valve open prior to using. However, I ignored this and used it to fill my tank for extra flushing. I'm wondering if this added too much pressure and caused a leak?
When I tried to look up under there, something fell into the wheel well. I think it was some sort of "cap" on top of a vertical vent? the top has a spring loaded something?
I can't be more descriptive because I can't see it.

Any body know something about this?

p.s. It looks like the cabinet would have to be taken out to get to the plumbing?
I can't see a way to get it out. Help?

was it clear? This is the check valve which is prone to leaking and I recommend eliminating and replacing with elbows and line as discussed above.

Landrum · 07-16-2013, 07:22 AM

I've never used our flush system, but our 23fb was in for service and the dealer found a leak in the anti-siphon valve. It is between the flush connection and the black tank and on our 23fb it is located right behind the sink. That might be your problem. I'm pretty sure I've seen other posts about that device leaking, so it may be a common problem??

**jcanavera** · 07-16-2013, 08:16 AM

I used my black water flush for the first few years of ownership on my last campout of the season. I finally decided that it probably is unnecessary if you practice proper dumping techniques. In my old HiLo which I owned for 14 years, I never had an issue with the toilet. I do make a practice of always dumping the toilet full. If it's not full, I fill it prior to dumping. Secondly on my last campout of the year I use a full hookup site. I dump the tank full, and then fill it again with clean water and dump a second time.

Jack

Bellah · 07-17-2013, 08:59 AM

Thank you.
Yes, it was the clear valve leaking.
Am I correct that if I don't use the flush system, there's no need in fixing/replacing the valve right away?

p.s. I found the "thing" that fell. It was a cap that fit on top of another valve. Seemed to be purely cosemtic. Anyway, I put it back on but it wasn't related to the problem.

Other posts have verified my suspicion the the flush spray didn't really work that well.
I think I'll just fill-n-flush from now on. The consensus seems to be that it is the best method.

Thanks all for the help.
JBell

dznf0g · 07-17-2013, 09:57 AM

Yes, if you don't use the flusher, you can postpone repair. I believe it is code to be there for the mfr, but that doesn't mean you have to keep it. There is an additional check valve at the garden hose fitting, and if you are still worried, you could add a valve to the end of your garden hose. It is EXTREMELY unlikely that you would have a siphon action, even if you filled the black tank to full capacity, which is silly to begin with.

markdoane · 07-17-2013, 11:49 AM

Quote:

Originally Posted by dznf0g

Yes, if you don't use the flusher, you can postpone repair. I believe it is code to be there for the mfr, but that doesn't mean you have to keep it. There is an additional check valve at the garden hose fitting, and if you are still worried, you could add a valve to the end of your garden hose. It is EXTREMELY unlikely that you would have a siphon action, even if you filled the black tank to full capacity, which is silly to begin with.

It's code. That means you should keep it. Whether you have a siphon action or not has nothing to do with your trailer, your black tank, how full it is, or when when you last changed your shirt.

A siphon can occur when anyone else in the campground, municipality, or fire district does anything to reduce the mains water pressure. More likely to occur at a campground, where water distribution system may not be as well designed as in your home municipality.

If that happens, you won't make yourself sick, but you could give everyone else at the campground you just left a serious case of E. Coli.

Don't take chances.

dznf0g · 07-17-2013, 01:06 PM

Quote:

Originally Posted by markdoane

It's code. That means you should keep it. Whether you have a siphon action or not has nothing to do with your trailer, your black tank, how full it is, or when when you last changed your shirt.

A siphon can occur when anyone else in the campground, municipality, or fire district does anything to reduce the mains water pressure. More likely to occur at a campground, where water distribution system may not be as well designed as in your home municipality.

If that happens, you won't make yourself sick, but you could give everyone else at the campground you just left a serious case of E. Coli.

Don't take chances.

I doubt it....especially if you take other anti-siphon action. And you would be using the same hose that you wash out the sewer hose with, which is already contaminated and has it's own anti-siphon valve at the top of the tower, some 10 feet in the air. Besides I only use my flusher at season end before winterizing in my yard with 150' of hose, the already there check valve in the trailer connection AND an anti-siphon valve on the hose end.

When I looked into replacing the AS valve, I called the mfr directly. (Can't remember the name, but seem to be a mom and pop operation) He actually talked me out of BUYING one saying it wasn't necessary due to the routing of the lines and the location of the sprayer head.

BTW, this brings up another point, I realized last year, because of the check valve at the hose connection, it is advisable to blow out the flusher line while winterizing. It will hold water in about 4-5 (in my case) feet of line up to the top where the anti-siphon valve is (was).

dgates1 · 07-23-2013, 09:39 AM

I have the black water swisher that comes with the unit.
Mine did plug up over the winter.
Any ideas about cleaning it off?
Davis gates
2005. Safari 28

Gene · 07-23-2013, 03:09 PM

Since I don't know about the 19' plumbing, I can only say to check the fittings under the sink for a leak—run water into the sink and see if you can find a leak. Fill the sink part way and then let it all drain at once. The P-trap under the sink or one of the pipes attached to it may have a loose fitting that needs to be tightened. It can be done by hand. Ours started to leak after a few years.

A drain system is not designed for high pressure, so a loose connection that gets a sink full of water at once can leak if not tight enough. A full tank could back up and put pressure on a fitting, but it usually shows up in the shower first since it is the lowest point in the system. I assume a 19' has a shower. If you have one tank (grey and black together) you don't want to see the results of a backed up drain system.

I don't know if this helps, but loose fittings are not uncommon in sink drains—either not tightened sufficiently at the factory or loosened by travel. It happens at home too because sink drains like to loosen over time too. A loose fitting is the simplest thing to check.

Gene