Sink won't drain

[BFlinn181]

Don't use Liquid Plumber then use an air hose!!! Also, if, as K7JV posited it might be a kinked drain line in a slide, the LP will do nothing to unkink a corrugated drain. The liquid plumber or Draino should cause no issues with the plastic drain pipes or tank, but could cause issues with tank gate valve seals.

To answer one of the OP's unanswered questions, the AAV is under the sink in the cabinet. It often is unscrewed by just hand pressure, use a strap wrench if more leverage is needed. Caution, don't remove it and pour water into the sink, if the line is blocked it will just back up in the AAV branch and flood your cabinet. Typically an AAV (cheater vent) malfunctions when it doesn't seal properly and allows sewer gas into the space. They seldom fail to allow air in, if they do, it would cause gurgling and perhaps drain the trap, allowing sewer gases into the area. I've never heard of one causing a drain to fail to allow water flow at all.

[wa8yxm]

Have you tried dumping the waste tanks.. I often have that problem in the kitchen.. and so far (it's been 9 years) that has fixed it every time.

Another issue is the drain itself,, Sometimes "Stuff" (just what depends on which sink it is, Bits of food, (pasta is real good at this) Hair, other stuff) get on the drain's strainer and clog it.

As for compressed air.. The danger here is that supply side plumbing can usually handle 50 PSI no tribble, but the drain lines are not nearly as well connected,, You can blast them apart with that kind of pressure. They are just rubber slip rings over plastic pipe and slide right apart.

Page 2: There are products that are basically Compressed gas in a can with a fitting that will seal it to the drain before you press to SHOOT a shot of pressure into the lines.

They also carry warnings about blowing the pipes apart I might add.

Plungers work best on the SUCTION side of the operation by the way.

[Gorlininc]

Use a snake at the air intake valve under one of your sinks. It's the inside vent. It allows snaking right to the tank. Just did mine.

[vavitro]

Yes, the coach was level. I think it's what Jim & Angie said. It's in the slide and we had that slide out recently. Before we had it out, no problem. After it's back, no draining. I think that's a good place to start looking.

[vavitro]

Probably won't use an air hose. I'm not even comfortable with chemical warfare (Liquid Plumber) since I don't know what's downstream that it might damage.

[vavitro]

We have not dumped the tanks yet. They are still where they were when we bought it since we haven't really gotten to do anything yet except "fix stuff". Right now, the Norcold is dead. Before that, the Onan threw a belt and all the batteries had to be replaced. I'm hoping this isn't going to be a money pit with one problem after another. It was used regularly before we bought it, so it isn't a problem of sitting unused that's causing all of these things. As one person put it, they are very complex and sophisticated with a lot of moving parts and pieces designed into it. It's not off-the-shelf DIY. Sigh.

[vavitro]

Jim, the hall sink is in the slide and we just had that slide out to get to the breaker box to see if the Norcold could be reset from there. It's another ongoing problem. The sink just happened before we could get the refrigerator assessed. Kind of been one thing after another since we bought it in August and we haven't even gotten to take one trip in it yet. When we get it back from refer repair next week, we'll put the slide out again and see if the hose you mentioned is visible. This seems the most likely thing to date of any suggestion. Thanks so much for sharing your experience. Fingers crossed.

[PRR]

When we had ours out for the 1st time the shower drained fine for the first few days. The park we were at didn't have level sights. The curbside rear hydraulic hose for the cylinder had a leak. Over that time the coach settled down hill on the curb side . My wife was taking a shower and it wouldn't drain. When I took off the access panel at the bottom of the shower, removed the p trap and found nothing, ran a snake down it and found nothing. Looked at the grade of the pipe and then went to see if the coach was still level. It was not. I leveled the coach and the shower drained. I would be cautious using compressed air to check repair this as it has the potential to do some damage.

[mel s]

Originally Posted by PRR

When we had ours out for the 1st time the shower drained fine for the first few days. The park we were at didn't have level sights. The curbside rear hydraulic hose for the cylinder had a leak. Over that time the coach settled down hill on the curb side . My wife was taking a shower and it wouldn't drain. When I took off the access panel at the bottom of the shower, removed the p trap and found nothing, ran a snake down it and found nothing. Looked at the grade of the pipe and then went to see if the coach was still level. It was not. I leveled the coach and the shower drained. I would be cautious using compressed air to check repair this as it has the potential to do some damage.

When I bought my coach, (at 5 years if age with 27k miles), the shower drained slowly.
To my surprise I found that the the P-trap was clogged with wood shavings and sawdust left by the skilled? Safari workmen!
In the 13 years, (108k miles), since I have found so many signs of sloppy workmanship and poor quality control, that nothing surprises me any more.
In fact, I have done so much, with so little, for so long, I am now qualified to do anything with nothing.
Mel
'96 Safari, 135k miles