Hi everyone. I'm the proud new owner of a 2018 Redwood 3921GK. I'm full timing in this unit and working out all the kinks. One huge annoyance is the draining of the kitchen sink. The sink is a large double bowl stainless steel sink. If I run water from the faucet into one of the bowls the sink drains fine. My issue arises when I fill the sink and then remove the stopper to drain the water. The water will start to drain and then it starts coming up in the adjacent bowl. The sink will eventually drain but it's very slow. If I have water in both sinks and I drain them it is also very slow to drain. It seems that there may be some sort of vacuum/pressure lock that is preventing the sink from draining. The plumbing of the drain pipes seem odd indeed. Since there is a shelf directly under the sink so there is no p-trap under the sink. This unit does not have the dishwasher. Any feedback would be greatly appreciated.

Well...It could be a couple of things...

First, Congratulations on your new rig and the new lifestyle!

Since you indicate it is new, has the sink performed this way since it was new? Or has this just started?

You might start with the pipe itself. Redwood is not known for providing you a clean rig at purchase. Check your A/C ducts as well. The sink could be clogged with sawdust...

Aside from that, I would suspect a problem with the waterless vent trap. Look under the sinks. I'm not sure which cabinet set you have, but on the 38GK, the waterless vent trap is located behind the spice rack. It could be bad. It could be clogged. In any case, you have a vacuum problem. You're not getting proper venting to the tank. This is where I would start.

If you are interested in how it works:

https://www.youtube.com/watch?v=tDNh7lfcIYQ

And another article:

https://blog.wavin.co.uk/why-choose-hepvo-the-benefits-of-a-waterless-plumbing-trap/

As you can see, the opening is not very large.

From here, water heads straight to the tank. I'm assuming your tank is empty?? 🙂

Man Gipc
You have way to much time on your hands. Wish I we retired

Man Gipc
You have way to much time on your hands. Wish I we retired

This all started with you and the rest of the early members from the previous Redwood site. I learned a lot from you guys (Thanks!) and I have attended Terry Cooper's Training classes (Thanks to Terry). Not to mention 100 years of Construction and Maintenance experience (At least that what it feels like). I did this to prep for the full-time living. RV's are so different but yet so the same. I figured that if we were going to hit the road, the last thing we needed was to be stranded and not have a library of information to pull from. As I do the work (no thanks to Redwood), I document as I go. Thanks to all of you for your valuable input.

BTW... I wish I was retired. We're full time in prep of next year. But not retired .... YET! All I need is a reason though...

GipCTravelers I do have the island with the spice rack and I'm pretty sure I can see the vent trap although I haven't removed the rack yet. My coach has been doing this since I took delivery of it in August. This is covered under my warranty but I've discovered it's hard to schedule it for warranty when you live in it. Lol. Unless I have any major issues I was hoping to compile a warranty list and have things fixed this upcoming spring. Do you have any experience with Redwood honoring warranty work via mobile RV service?

Perhaps I'll just pull the trap to see if its clogged. Thanks for the info!

Lol Woody! You'd be surprised how busy you can stay, even after retirement!

I understand the full-time living well ... now ...

Getting it to the dealership will be a pain. Usually, if you purchased from the dealership, you can work with their service department on warranty and get a quick turn around. If you were to take it to someone else, you could be in line for months.

I get it with warranties, but you just sometimes have to pick your battles. This is one that will only take an hour or so, but the hassle of getting the parts will add time. And then there is the $100 (with tax and shipping). Maybe Redwood would send you one direct? Like you said, maybe you can just compile a list for a future return to the dealership. I'm sure there will be other things...

Recently, we were discussing another warranty issue with an individual in Michigan. I had suggested checking with Redwood to see if they would work something out with a mobile tech. At one point, they would. But as of the recent posting, they would not. It's still worth a phone call. Especially since you are full time and just bought it.

http://redwood-rv.com/contact

First check to see that they installed that vent correctly, as not upside down, some of those guys aren't the sharpest pencil in the drawer.
As far as warranty for us fulltimers, my suggestion is if it's something you're comfortable fixing, do it. In any case don't let your dealer keep your RW more than a day to make a list, check twice & then decide if you're going to be naughty or nice. Most dealers famous excuses are " we're waiting on parts" or "waiting on authorization" both of which mean "we'll get to it when the customers raise so much hell we better do something, maybe". Have them order all parts necessary & schedule a date do everything in one day. Call RW & confirm the dealer has got authorization & has in fact ordered parts.
As GipC said it doesn't cost anything to ask for a mobil tech, probably get a better job from,one.

First thing I would do is pull the Hepvo unit out and make sure that the large opening is at the to with the flexable insert pointing down.
We had the same problem with our dual bathroom sinks and when I pulled the Hepvo unit the insert was turned inside out. Cleaned it up and pulled it back down where it belongs and problem solved.

From the HepvO Website (Installation, Maintenance and Troubleshooting)::

http://hepvo.com/installation-maintenance/

Blockages

If a pipe blockage occurs downstream of HepvO we recommend temporarily removing the HepvO valve before rodding the pipeline. If the HepvO is rodded there is the possibility that damage to the internal components will occur.

Maintenance-Cleaning

No routine or seasonal maintenance is required for the HepvO sanitary waste valve, however, should you blow-out your drainage lines do not exceed 80-100 psi.

HepvO is resistant to standard caustic-based drain cleaners. It is also resistant to acid-based cleaners with concentrations up to 10%. When flushing with higher concentrations of acid based cleaner, the valve must be removed before the operation.

If mechanical drain cleaning devices are to be used it is necessary to first remove HepvO from the waste system. This provides a useful access point for servicing downstream pipework.

It is good practice to rinse the HepvO valve with clean water after any maintenance procedure.

While you have the spice rack removed to access the Hepvo be sure to check the auto vent or cheater vent attached near there. If it doesn't work properly the tank could become hard to fill because if the air can't escape then the water can't go in the tank.

They can be replaced with better and more expensive ones, although they can usually be cleaned with soap and water and put back into service.

Chris
2012 36RL

Those are typically under the restroom sinks but not the kitchen sink. Does your unit have one? It would have to be installed higher than the sink (close to the bottom of the countertop or above countertop level) or it could flood under the cabinet.

I have one in the bathroom and one under kitchen counter behind the spice rack. Ha e replaced both as the original ones were junk