201QB tank sizes

BK

bkenobi69@yahoo.com

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Question: I only have single fresh, gray, and black tanks in the trailer as far as I know. The sensor panel has a button for monitoring fresh, Gray 1, Gray 2, Black 1, and Black 2. Ar Gray 2 and Black 2 just there and not connected to anything? Or, are they wired to the top half of the Gray and Black tanks?


Reason I ask:
My 2019 201QB has a panel with buttons for monitoring fresh, Gray 1, Gray 2, Black 1, and Black 2. I took the trailer out last week with a full fresh tank (listed at 52 gallons) and all other sensors showed empty. After about a week, the fresh tank was down to 1/3 full which seemed about right. When I was cleaning up to head out, I used the bathroom sink and noticed that the shower was making noise and saw a little water come out of the drain. I thought the sensors for tanks 2 were for the top of the gray/black. Either the gray tank (listed as 39 gallons) was full or I have a venting problem.


The tech at the dealer told me that the second tank (if not installed) will just read empty at all times and that if Gray 1 read full, then the tank was full. If so, no problem. I just want to make sure I know how the thing is built so I use it without issues.


I was thinking of getting out some 5 gallon buckets and dumping them down the shower drain until it acts the same so I can confirm both that that was the issue and at what volume it's topped off. That said, if the brochure is always accurate, I can skip it and just know that when Gray 1 says full, just be ready to dump (obviously).
 
I added water to the gray tank using1 and 5 gallon containers. At 16 gallons it indicated 2/3 full. At 21 it was full. I added 2 gallons to the bathroom sink and the shower started to back up. I waited a while and it drained itself but still shows full. I added 2 gallons again and it backed into the shower again before draining.

Gray 2 still shows empty so i assume that tank is not connected. But i don't understand why the brochure would claim 39 gallons when its clearly closer to 20. Also, does the slow drain suggest that its leaking somewhere or just that the vent stack could be blocked? In a house plumbing there is a vent to the roof for proper flow and as far as i can see the trailer is the same. I dont see anything under the trailer so im assuming its going to the tank slowly.
 
Kodiak design and build is the poorest in the industry.
1) I put short pieces of black electrical tape over the unused "tank"2 buttons and labels. It looks a lot better.

2) I guess the same as you. There is probably a venting issue with the gray tank.

Assembly line workers on the run (literally) are not the best plumbers. Missed steps are par for the course.

Vents have been found to have slipped down into the tank, cutting off filling to the top. They should be firmly glued in place. They are not always. You may be getting slow venting past the unglued vent into the under floor space.

You may or may not be able to see it by removing the roof vent cap. Pipe should reach all the way to the vent cap. Any gap means it has slipped.

Anyway you look at it, your test proves it is defective. You will have to be "persistent" in order to get warranty from Kodiak, Keystone, Voltage. They may give you all sorts of push back. Be firm, answer all questions with confidence even if you are not sure. Doubt will likely be exploited.

No telling what the service people will find when they open it up. In mine, the under floor heat pipe hole was not drilled all the way through. Pipes froze even when heat was "ON". Freeze damage was not warranted.
 
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I'm 2nd owner so imagine they would blow me off anyway. Is there a way to access the vent on top of tank? From what I'm seeing in the cabinets and under dinette the tank is below floor with no way to do anything. I'd have to drop the plastic under basement and drop tank to access top/vent. Sounds like they probably messed it up in an unfixable way.
 
In 2018, Keystone agreed to pay the dealer who sold me the TT, $400 to remove the belly panel, fix the heat hole through the floor and put it back on.

It is not something I would attempt to do myself, but other owner's have done it.

The holding tank would also likely need to be removed, repaired and replaced.

One owner reported he could pull the vent pipe up to the cap and fasten it on top. This would not seal the unglued joint and risks pulling the pipe out of the tank altogether. It did restore the holding tank capacity.

I have never tried to remove the vent cap on mine.

If the TT is less than 1 year old you may be able to get warranty coverage. Again be persistent and confident. Read the warranty found in the TT owner's manual for best advice.
 
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It's a 2019 and I got it in 2022 so it won't have a warranty. The dealer suggested an extended warranty may be available but not sure if that would be worth getting or if it would cover this either way.


I am going to use my inspection camera up the drain and probably down the vent to see if I can learn anything. If it's the vent tube, hopefully that's something that can be fixed. I looked in the driver's side cabinets and see there are 2 vent tubes that appear to be connected to the black and gray tanks that run right next to the refrigerator/furnace. The gray appears to be almost vertical so perhaps I can just reach in and pull up to see if it's loose or not. If the pipe wasn't glued, then that means that the water would reach the vent tube position and vapor lock until the air could sneak out the unglued area around the tube. If so, then that would explain the very slow drain and no water collecting elsewhere.
 
The vent on the roof has a cap that says "pull to remove" but appears to have silicon over a depression on one side. I'm assuming there is a screw in that hole that must be removed? I looked inside the cabinets to see if the vent tube can slip up/down. The kitchen sink drain line tees into the vent line at floor level so it doesn't look like it could slip down. It's also tied in place with zip ties so i don't think venting is the issue.

Keystone confirmed the tank is 29 gallon and recommended a camera in the tank through the dump drain, shower drain, or the vent. The sensors showing full means something funny is going on. Maybe the empty sensor is out and it doesn't fully drain? They recommended either talking to the dealer or a mobile tech.
 
I pulled the cap for both tanks and the tube is at the top as it should be. The gray is slightly short but that's just shoddy work and not the pipe slipping down.

I tried to get the inspection camera down the pipe into the tank but it appears to get stuck at the tank inlet. Ill look again tomorrow when i have some time.
 
Good question. I don't recall seeing 1/3 full. I only checked at 16 gallons. Would be easy enough to check. Ill add around 10 gallons and check.

I can't get the camera into the tank from the vent or the dump valve. I guess i could try the kitchen drain. Pushing a flexible cable doesn't work all that well...
 
Does anone have a wiring diagram for the sensors? I found some for other mfg but not sure if they are universal.
 
I went a little overboard and added 1 gallon at a time to see where the sensors triggered. When empty, the sensors show empty. When I add 5 gallons, the 1/3 sensor lights. At 11 gallons, the 2/3 sensor lights. At 21 gallons, the sensors indicate full. I put a camera down the vent stack as far as I could and added another gallon and the water in the vent stack increased height.


I noticed that at around 15 gallons there was some gurgling happening after adding each gallon of water. I was adding the water through the kitchen sink which is a shared connection with the vent so it's possible that the noise was because there was no place for the air to escape from the tank and bubbles had to bubble through the added water to get out the vent stack.


So at this point, it looks like the sensors are working and the vent is correct. The tank the mfg claims to have installed is 39 gallon yet it does in fact fill up at 21 gallons. So as far as I can tell, there is a 18 gallon tumor inside the gray tank. :confused:
 
The mystery deepens. I pulled the nails and screws aft of the wheels on the passenger side so I could pull the black plastic down enough to measure the gray tank. Although the opening was tight, it appears the tank is approximately 48x27x7 inches or 9000in3 which is 39 gallons. If the tank is correct then there is either a ventilation issue or something in the tank (18 gallons worth). What is confusing to me is that the 1/3 and 2/3 lights come on at 5 and 11 gallons. If the vent was too far down then the sensors would indicate 1/3 full at 13 gallons, 2/3 at 26 gallons and full at 39 gallons but never get to whatever light is above the vent height, right?

But maybe it's more complicated? The tank has 2 inlets as far as i can tell. One inlet is the vent and kitchen sink. The other inlet is the bathroom sink and shower. If the bathroom inlet ends above the vent, then it would become the vent. Since both shower and sink have a p-trap, when more water is added the air would have to bubble through the trap. And, at around 18 gallons i started hearing gurgling.

Too bad it's not under warranty because they should have pulled the tank and fixed the mfg issue. I don't see much of an option other than pulling the tank really.

But how would that happen since the two inlets are glued on inside the cabinets? Does it have to be gutted to access it? There are 2 inlets (below dinette and under fridge).
 
"What is confusing to me is that the 1/3 and 2/3 lights come on at 5 and 11 gallons. If the vent was too far down then the sensors would indicate 1/3 full at 13 gallons, 2/3 at 26 gallons and full at 39 gallons but never get to whatever light is above the vent height, right?"

Many fill level gauges are where ever the installer drilled the tank and installed the sensor. You may be able to see the wire connections on one side of the tank.

"The tank has 2 inlets as far as i can tell. One inlet is the vent and kitchen sink."

The kitchen sink should have a p trap with a "T" connection to the vertical vent pipe. The vent pipe should go up to the roof. This prevents the p trap from being sucked dry when there is high water flow.

This part of the plumbing may be working correctly. Try filling the gray tank through the kitchen sink. If you get 35 gallons or so through the kitchen sink drain, then this part is working correctly.

Don't try to dump a whole 5 gallons at once. That may block the pipe temporarily until it drains. You should be able to get a substantial flow through and still allow air up the vent pipe.

"The other inlet is the bathroom sink and shower."

This part of the plumbing is not working correctly.

This assembly should also have a vertical vent. The p traps should run horizontal into the vertical vent. Again this prevents the p traps from being sucked dry.

The shower may not need a vent since its p trap is so close to the top of the tank below. A plumber would know the exact details.

There is another possibility. The p traps could run horizontal to a vacuum break air admittance valve. The valve would suck air when high water flow is present. That would prevent the p traps from being sucked dry.

You may be able to find the air admittance valve under the bathroom sink.

The air admittance valve may be stuck and not allowing air in.

This assembly may be partially blocked before it goes into the tank below. So air bubbles out of the shower drain while the pipe is filling up.

Try inserting your snake camera into the drains to see what might be blocking them.

Try running a plumbing snake through the drain into the tank. There may be a hair ball in there.
 
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The first time I tested the tank capacity I dumped water into the shower because i was using the 5 gallon bucket. If I put that in either sink I thought I might make a mess. Since I was adding 1 gallon at a time from a hose outside this time, I used the kitchen sink since it was closer. So in either inlet I'm seeing the tank full at around 20 gallons.

Ill look under the bathroom sink and shower to see if there are any check valves. I'm no plumber so I appreciate the suggestions!
 
I pulled the cabinet panel covers so i could look by the vent/kitchen sink inlet. The sink runs into the vertical vent and connects with a T. I taped the inspection camera to a flexible nylon snake and was able to get down the vent to what looks like a horizontal panel. The end of the tube to that panel was only a couple inches.

The tank is 7" tall. If the vent was inserted past the top of the tank and only 2" from the bottom, that could make the volume of the tank much less. If the tank were 4" deep because of that, I would only have around 20 gallon capacity.

I looked by the bathroom and kitchen sinks and there are air admittance valves valves.

I have pictures and video in the vent tube but not sure they help. I could post if anyone wants to see them.
 
So you are saying the vent is too low (as we expected)? I can drop the corrugated plastic but getting the tank out seems near impossible since the plumbing is not accessible yet glued in. Any suggestions that don't include an accidental fire? Lol
 
Can you access the pipe to tank fitting at the top? You may need to increase the size of the hole in the floor to work.

It may be glued. Cut the pipe. Remove the glued joint. Replace parts as necessary.

Fitting may be threaded to the tank. Cut the pipe. Unscrew the fitting. Remove the pipe that is too long. Replace the parts as necessary.

It also could have a compression fitting at the top. Loosen the fitting. Pull the pipe up. Cut pipe off. Re-tighten.
 
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