T@b 400 Convector Locations

bergger

The other day I finally uncovered our 400 and began my preseason checks.  One of those checks is to uncover the convectors and look at the connections the best I can for obvious signs of swelling and or leaking.  Looked the same as the past few years so I'm happy with that.  Anyhow, this time I took some photos of the locations and the convectors on our 2021 400 so newer owners or anyone who is unsure of the locations will now see where they are.  As far as I know the number and locations of the convectors have not changed over the years, at least the last 4 or so.  

The 400 has 6 convectors.  The glycol flows from the Alde in a counter clockwise direction.  The first convector is enters is the long one at the back of the trailer behind the bed.  It can be somewhat accessed by removing a couple of screws securing the rear most bed panel.  It is further covered with another thinner piece of wood.  I simple stuck my phone behind that to take photos and also felt the stubs with my hand. On the 2021 400 this is also where one of the two bleeder tubes is located, on the door end of the convector.  The bleeder tube can be accessed by reaching down and feeling for it without removing anything.  Here are some pictures.





The next convector in the loop is the long one under the kitchen.  One end of it can be viewed by removing the lower deep drawer, just above the converter box.


The other end can be viewed by removing the protective box under the kitchen sink.  It is secured with 4 screws.  There is a bleeder valve here but no bleeder tube.  Starting in 2022 you should see a bleeder tube so removal of the protective box is not necessary to access the bleeder valve. 



The next convector is on the other side of the entry door behind the passenger side dinette seat.  This one you must remove the dinette seat panel to view and it also has a bleeder tube.  In the 2nd photo you can see the tube and it can be fished out for access to the valve.  For complete access to everything I believe you'd have to also remove the soft wall panel.  




The next convector is covered by the wooden box under the dinette table.  This box also conceals electrical wires and the Cool Cat ducting than vents out near the trailer door.  This box is very difficult to remove as you must first remove the visible screws, then remove both seat panels for the dinette then 4 screws contained under those panels.  Even after all than you can't really get it off as the wiring, ducting and the convector are actually attached to the wooden box.  Not only do the screws hold it in place but all this other stuff does as well.  But you can see enough to inspect the convector.  There is a design flaw with the heat venting in this box that I notified NuCamp of long ago but I don't believe they ever corrected it.  The cutouts that allow heat from the convector to escape is essentially completely blocked by the Cool Cat duct work.  The venting should be on the front end of the box directly over the convector.  I was able to move some of the ducting out of the way but not as much as I wanted.  I do not have any good photos of this convector.

The glycol then travels up to the expansion tank then out and into a convector behind the drivers side dinette seat.  This can be accessed by pulling the cushions and removing 4 screws that secure the thin wall panel.  You can also remove the three screws that secure the seat panel to uncover the Cool Cat and see more of the glycol piping. Notice in the last photo where they even put felt pads behind the piping where it comes into contact with the wall. 





The glycol then travels to a convector under the bathroom floor which can be viewed by removing the access panel under the bathroom door.  



It then flows up into the bathroom.  There is no convector in the bathroom but simply some of the black rubber tubing with a bleeder valve.  This tubing is under the plastic cover just under the shower.  The bleeder valve can be accessed by removing the two screws in the top plate cover.  A micro ratchet with the correct fitting is best to remove this cover.  The glycol then returns to the Alde.  

Well hopefully someone finds this helpful or at least interesting.  All of this stuff can be accessed by just removing a few screws.  I encourage owners to open things up and see where they are and make sure nothing looks out of norm.  One thing I am always reminded of when I crawl around my trailer, and yes I crawl up and under it to inspect every visible screw and bolt, is how well these things are built.  They really are built so much better than most other trailers.  Who else uses 1/2" baltic birch to build a protective box hidden under the kitchen sink.  Or doubles up 1/2" baltic birch to build the simple slot that the Cool Cat filter slides into under the dinette seat.  No staples, mdf or wafer thin wood in this product.  

Robermcm

Thanks. I enjoyed the counter clockwise tour!  @ScottG and I were just discussing glycol direction. I’d gotten confused in conversation at the Truma Elkhart service center. He got me straightened out with counter clockwise as fact!

Agree with the quality thoughts. The Truma techs made the same comparative observation when I was there. And they see all brands, I think. 

When I crawl around, I often find semi loose plumbing fixtures. Those twist tight connections would benefit from some thread lock ‘product’. Not sure which one. And where is the cool cat filter slot? I have a spare black filter but haven’t found its home yet. Thought it might be accessed from the outside, but that’s illogical. 

BridgerSunset

@bergger,

As an owner of a 2021 400,  I've taken apart a few of these panels to look at connectors.  But I never had the guts to dig for the others.  Thank you very much for taking the time to document this.  It's  very helpful & gives me the optimism to tackle an inspection for the remainder!

bergger

@Robermcm if you lift up the drivers side dinette cushion you will see a hinged access panel.  The filter is right there.  The filter is contained in a hard plastic frame that slides out of the built in groove.  

Robermcm

bergger said:

@Robermcm if you lift up the drivers side dinette cushion you will see a hinged access panel.  The filter is right there.  The filter is contained in a hard plastic frame that slides out of the built in groove.  

Thanks. After I posted, I went out and found it. I’d opened that hatch but never saw the narrow dryer lint vent style filter up against the wood. 

pthomas745

Bergger, I think this is entirely useful.  Since digging into the "corrosion" situation in the Alde 3010 trailers, and the changes since early 2021 with the glycol, I have noticed the way that the convectors, hoses, pipes, etc in the Aldes have changed quite a lot.  Even in your photos, it is an obviously better designed and installed setup compared to the hoses that "seemed" to be slapped together in the 3010 trailers.  I would really like to examine a trailer from the last few years to see things like the pipe and hose fittings, clamp positions, and all the rest. 

If the Forum's work on the corrosion of the convector stubs is the proper way to go, as far as the coating of the stubs and the better, more secure clamping, it would be interesting to see how the Alde's design changes helped to prevent corrosion, and if they coated the stubs themselves.  They must have learned quite a lot from the failures seen in the Tabs and the Airstreams to convince them that something was incorrect in part of their design or construction.

I'd like to see every hose and connector, personally!

bergger

I'd like to see a new trailer with the Alde 3030 installed to see how the plumbing is installed.  It certainly does seem to be improving over the years.

The next thing i have to figure out is how to limit the loud rumble/vibration that happens when the Alde kicks on in very cold weather.  It was 24 degrees out the other night so the heat kicked on quite a bit during the night.  That 5-10 second rumble is loud enough to wake us up just about every time it happens.   To me is seems to come from the exhaust/intake vent so I'm thinking of putting some type of foam insulation around it to try and minimize the vibration. 

barbarella20722

@bergger Thank you for posting this. It will help me greatly going forward. I have a 2020, 400 with the air8. I've just started dealing with the corrosion issue plaguing other owners. Am I mistaken or does your rear convector have metal tubing on either side? I ask because mine doesn't. There's data to suggest that hoses installed with a slope like mine, are more prone to corrosion. Hoses that are properly clamped and installed with no downward pressure are less likely to have buildup over time. This seems to be true to an extent. The rear convector was a mess but the one under the wetbath had only minor corrosion. So far I've only taken apart the two I've mentioned. Here are some pics of where I'm at so far.

your picture.


Under the bath.

The one I pulled from behind the bed.

How it was originally installed.