Last Updated: 01/01/2022

Today the Webasto X100 Diesel Cooker got some serious testing done, and for a very good reason.

Back when I did purchase it, I didn’t really pay too much attention to the installation manual. Yes, I did read it from cover to cover but one important fact did managed to escape my attention. In the installation manual there is no mention in writing of this particular requirement but on page 16, Figure 21 does tell you a very specific limitation of this unit: the distance between the exhaust outlet from the cooker and the end of the exhaust must be not higher than 1.2 metre and a maximum length of 1.9 metre.

I couldn’t believe it! I had purchase a very expensive Diesel cooker that I couldn’t use, unless I wanted to have an exhaust right under the kitchen window.. No! There is no way that I was going to have to close the window every time I started to cook. Does this mean that the Webasto model X100 is designed only for small vehicle where the 1.2 metre drop is standard? It just didn’t make any sense.. After some good search online, it seem that the Webasto X100 unit is just a Wallas 88 DU unit (but not as easy to install as the Wallas)..

Actually the Webasto X100 does look exactly the same as the Wallas 85 DT, but the 85 DT does not have the underbench box

So if you don’t want to read the whole review and you are in the market for a Diesel cooker and don’t mind the rear gas discharge, the Wallas 88 DU is the way to go, as it is much easier to install and/or simpler to service, if you prefer! There is also the Wallas XC Duo, if you need an heater combine with the cooker..

All these units are identical as far as power, fuel consumption and design but for some reasons that I can’t comprehend, Webasto managed to stuff it up. The Wallas unit is one piece. You cut the benchtop, drop the unit in, four bolts, two plugs, one exhaust, the fuel line and you are ready to go. To service it is just a matter of reversing the installation order and the unit just comes out.

The Webasto has being split into two completely separate pieces. The unit itself and a metal box (they call it the cooling unit as it has a fan on the front). To install the Webasto you need to cut the benchtop, drop the unit in, again the same four bolt, then you will enjoy yourself trying to attach this metal box on the underside of the bench by using 14 (yes 14 screws) including the 4 at the back of the unit, where you may have 25mm space (like I did), between the metal box and the back of the cabinet. Beside being a major PITA, you also need to remember that around every 500 hours the unit has to be remove for service.

Oh great.., I’m really looking forward to those four screws at the back in two years time.. And imagine how good those screws will held considering that the cabinet is chipboard. The plan here, when the time come for a service, is to make the box a fraction smaller so to fit and work like in the Wallas unit (88 DU), where the box is attached to the unit instead of the underside of the benchtop..

The X100 system also won’t work, as it is, if you benchtop is granite or stainless steel, unless you are willing to drill your granite or using rivets to attach the box.

Webasto also manage to misguide his customers as well with the exhaust length. I mean, the units are virtually the same (Wallas makes them all) and for some reason while the Wallas unit allows for a 2 metre exhaust in any direction (or 4 metre with an extra cooling pipe for the 88 DU), Webasto reckon 1.2 metre (vertical) is the limit and yet, Wallas (the manufacturer) gives you a 2 metre stainless steel exhaust in the package. I had the feeling after reading the two identical manuals, (except for the lack of some error codes and the wrong vertical length of exhaust in the Webasto manual), that the Webasto unit was going to be fine with a vertical 2 metre exhaust.

Sure enough, it does work just fine, and there is a good reason for it. Considering that all these units are built virtually the same, other than how the box is attached and the different name on the glass in the Webasto, and a two (or 4) metres hose is possible for the Wallas, there is absolutely no reason for the Webasto model to be any less.

I have tested the unit for six hours now, by boiling 12 times 4 litres of water in a large spaghetti pot. With the 2 metre vertical exhaust, I repeat, it works just fine!

As you can see from the picture on the right, that’s water boiling without the need of a lid. Every time it took an average of 25 to 30 minutes for the water to reach the boiling point, so I’m sure with the lid on the pot, the 20-25 minutes mentioned in the manual is quite accurate..

The next test will be to check what temperature each number on the dial actually gives you as it seem to be the same or perhaps it takes long time to record the change in the dial. The only difference I notice was the frequency of the fuel pump increasing a little when on 6..

I did managed to find another misguide info from Webasto in their FAQ question 22:

Q:   Where is the combustion air sourced from?

A:    Outside of the vehicle via the combustion air tube

Oh boy… The combustion air is provided by the second internal fan visible under the unit inside the box. It is like they are selling it but don’t really care much to make it right.. Do yourself a favour and just use the Wallas manual as it is actually the correct one in every aspect.

All units feature a controller with a power button and a dial. The Webasto also feature an extra button for altitude above 1800 metre. All the button seem to do, it increase the fan speed (combustion fan). Again people have reported no need to use the button even at 2500 metre high.. Maybe Webasto worked on an average… Who knows…

Now the good bits, because after all, this was meant to be a review of the cooktop…

Wallas makes quality products and this X100 (85 DT with the extra underbench box) works well and it use very little fuel. It doesn’t smell and it doesn’t heat up the room as much as gas does. It easy to clean, like most ceramic glass top and it does look good. Once you pass the obstacle of the installation of the box, it is actually very easy to setup and it doesn’t take too much room. One thing that I was originally worried about was noise either inside or outside the vehicle. Great news.. This unit is as quite as a mouse both inside the vehicle and outside where the exhaust comes out. The controller cables are long enough to allow the installation as you please. Like the manual suggest, the controller unit is best mounted vertical and away from possible water spills, as it is not a waterproof sealed unit.

Spare parts are available (from both companies) and also from other retailers and a service kit required every 500 hours of use, (including a glow plug, burner mat and fuel needle) will set you back around the $150.00.

If Webasto did managed to fix the under benchtop conundrum, it would be a great choice for customer that want/need a downward exhaust unit instead of backward like the Wallas. Or you could buy the Wallas 85 DT and make yourself an aluminium box to go under..

In conclusion, all these unit are very good diesel cooker, but remember that the Webasto will take an extra hour of your time, every time you need to work on it..

Built Quality
Ease of Use
Performance
Value for Money