Eberspacher/clone diesel forced air heaters

I've installed several of these units over the years in RVs strictly by the install manuals. I know they are popular with boats. I plan to have one or two aboard my boat. I stumbled upon this guys videos. He has a lot of videos based on the Eberspacher clones. He has experience with both plus the Webasto units. His videos go deep into the installation and making them last while also running quietly and reliably. He goes deep into how and why, and shows exactly why and how. He also has a good video on diagnosing and repairing the units. After seeing his videos I have more faith in the units and my ability to install them aboard my boat.


I hope his videos help others even if they never touch their heater other than to operate them. Remember the clones are near identical copies of Eberspacher and Wabesto units. What works for the clones should work for the name brands.



Videos. https://www.youtube.com/user/johnmck1147/videos


The video that really helped me with understanding the inner workings.

Ben - Thanks for the link. Great information. My Eberspacher has always been touchy but something I've lived with. These videos gives me ideas for future upgrades.

We looked at these recently. The issue seemed to be getting the hot exhaust pipe through the hull or elsewhere without burning the boat. One "original" version, can`t recall the brand, cunningly runs the exhaust line inside a wider tube comprising the air intake.
A marina neighbour fitted one to his small RV. Says he would have mounted it under the floor if he had his time over but, main concern is even on low, the RV gets too warm, so he opens a window. In a demo,it ran fast with some fan like noise, then throttled back to quiet. He seems pleased with it.

BruceK said:

We looked at these recently. The issue seemed to be getting the hot exhaust pipe through the hull or elsewhere without burning the boat. One "original" version, can`t recall the brand, cunningly runs the exhaust line inside a wider tube comprising the air intake.
A marina neighbour fitted one to his small RV. Says he would have mounted it under the floor if he had his time over but, main concern is even on low, the RV gets too warm, so he opens a window. In a demo,it ran fast with some fan like noise, then throttled back to quiet. He seems pleased with it.

Click to expand...

The Wallas furnaces (www.wallas.fi) are designed for boats. They have the intake and exhaust that you are describing.

The intake is a larger tube, and the exhaust is a smaller tube that runs inside the larger intake tube.

NWSeadog said:

Ben - Thanks for the link. Great information. My Eberspacher has always been touchy but something I've lived with. These videos gives me ideas for future upgrades.

Click to expand...

You're welcome. There's probably some minor issue causing it to be fussy. Really simple little heaters.

BruceK said:

We looked at these recently. The issue seemed to be getting the hot exhaust pipe through the hull or elsewhere without burning the boat. One "original" version, can`t recall the brand, cunningly runs the exhaust line inside a wider tube comprising the air intake.
A marina neighbour fitted one to his small RV. Says he would have mounted it under the floor if he had his time over but, main concern is even on low, the RV gets too warm, so he opens a window. In a demo,it ran fast with some fan like noise, then throttled back to quiet. He seems pleased with it.

Click to expand...

There are thru hulls designed specifically for passing the exhaust through the hull.


$55! Cheaper than I thought. There are a few sizes to chose from.
https://www.amazon.com/marine-stain...6add386b2e9cc840640ffdb0eb9844&language=en_US


The controller sets how fast and hard the heater runs when it's powered on to heat. There are several controllers available for the clones.

ksanders said:

The Wallas furnaces (www.wallas.fi) are designed for boats. They have the intake and exhaust that you are describing.

The intake is a larger tube, and the exhaust is a smaller tube that runs inside the larger intake tube.

Click to expand...

Those are good little units. Seems weird to have the exhaust and intake run together like that. I have an oil furnace in one of my mobiles homes that is set up like that and it runs to the roof. Nordyne took over Intertherm. They say my furnace is a poor design with many problems and I agree. I wonder if the smaller size of the Wallas is why they work so well. My furnace is rated at 80k to 120k btu depending on the fuel used. It can run on kerosene #1/#2,diesel #1/#2 propane, natural gas, heating oil #1/#2. All it takes is a nozzle change and setting the intake combustion air. I used #2 heating oil. It was the cheapest.

One advantage of the combined intake exhaust is the air being consumed is outside air , un heated , that you did not pay to heat.