Eberspacher or Webasto diesel heaters
Eberspacher created the first diesel air heater in the 1930's. The fable is that Ferdinand Porsche needed to be able to pre-heat his high performance air cooled Porsche engines in snow conditions (before starting the engine - to prevent damage), the Eberspachers were acquaintances and this is why the air heater was born. They then created water heating systems and these are still used today in Europe to pre-heat vehicle engines in sub-zero conditions. The air heater was an ideal candidate for use in RV's and caravans and this is where most are used in Australia and New Zealand.
Most European cranes imported into Australia come with a air heater pre-installed. We see mostly Eberspacher in this application but there are plenty of Webasto diesel heaters installed in these applications. Either are quite suitable.
Webasto started in the following decades. Whilst the 2 brands are slightly different in how they apply the fuel into the burner chamber they are fundamentally working under the same principle.When you first turn on a Diesel Heater, a good caravan heater like the Eberspacher , Webasto and Warmda will run through a check of its systems.
- Firstly the fan will run up to speed - this checks that the heater is not blocked or restricted in any way.
- Next the glow pin (or glow plug, if you prefer) heats up, if this all goes well, then the fuel metering pumps starts pumping. The glow pin has reached a temp of around 500 degrees Celsius, the fuel is injected onto a fuel screen that atomizes the diesel fuel, this atomized fuel then burns upon touching the super hot glow pin. The glow pin shuts down, but the heat in the burning chamber keeps the fuel screen and pin hot, and, the combustion process carries on. The fan speed and metering pump work in conjunction with each other to regulate how much heat is required.
All of this combustion happens inside the heater. The air for the combustion process comes from outside (underneath the heater), exhausting for the combustion process exits outside (underneath the heater).
- Air for heating the caravan is drawn over the heat exchange fins, heated and pushed out into the room. Air for combustion and exhaust fumes are kept separate from the cabin heating air to prevent any smell, fumes and gases reaching you.
- When you shutdown the heater, the glow pin is reheated and fuel stops pumping. This burns off any excess diesel so you have a clean start up next time. The fan continues to run, to cool the whole heater down. When the temperature drops to an acceptable level the heaters turns off completely.
So all good brands of diesel heater work in this very similar way. Any heater brand that suggests you need to conduct any sort of special heater shutdown process, is a poorly designed heater, as the shutdown process is a very important part of heater design.
Webasto AT 2000
- 2kw heating power
- 3 fan speeds
- Digital Control (newly introduced)
- 4000 + hours
- Access to fuel screen (heater must be removed and taken out of the cover)
- Access to glow pin (heater must be removed and taken out of the cover)
- Heater must be run at least once a month to prevent issues with the fuel screen "clogging"
- Well made, cast alloy and plastic
- Exhaust cast alloy and air intake half of heater is plastic
Back up and support
- Corporate office in Australia
- Reasonable number of service agents
- 2.2kw heating power
- 4 fan speeds (finer temperature control)
- Digital Control
- 6000 + hours
- Access to glow pin - easy, can be done without disassembly
- Access to fuel screen - easy, can be done without disassembly
- Well made, cast alloy and plastic
- Both exhaust and air intake ports are cast alloy
Back up and support
- Local Agent - Dometic
- Easy to obtain parts and support
Webasto or Eberspacher Diesel Heater - Eberspacher Airtronic D2 or Webasto Air Top 2000 STC
We generally believe the old maxim of you get what you pay for. Eberspacher is generally more expensive than the equivalent Webasto heater.
Fuel Metering Pump:
Webasto have introduced a new fuel quieter fuel pump so in this area they are now the same. Webasto has caught up.
Webasto have recently added a digital control, so again they are now closer in this area. Eberspacher heaters have 4 heat settings, with the Webasto having only 3 heat settings. So we see finer temperature control from the Eberspacher.
Warranty is 2 years on each so again they are pretty equal. However Webasto don't have the easiest reputation as a simple company to deal with. Both have some very good service agents, so this helps. Eberspacher takes a win here.
Neither heater has a scheduled maintenance period. However Webasto state no maintenance is required ! However this is simply not true, as we have found all heaters require servicing from time to time. Webasto also state you need to run their heater at least once a month. Not required on Eberspacher. The service port on a Webasto is also under the heater, so the heater must be removed from the installation and the plastic shroud completely removed to carry out simple maintenance. Eberspacher can be serviced in-place if required. So a win to Eberspacher here.
Both heaters are well made and constructed. The Webasto is slightly more difficult to service (as mentioned). There is more plastic construction on the Webasto (note the burner air intake port "half of the heater" on the Webasto being plastic). So a win to the Eberspacher. I think it should also be noted that most Chinese "clone" type heaters are fundamentally copies of the Webasto design, this is due to the cheaper cost of manufacturer.
Eberspacher is 2.2kw and the Webasto is 2 kw. We also see slightly more air volume from the Eberspacher on its highest setting. So a win to Eberspacher.
Lowest Power Consumption:
Eberspacher 0.7amps , Webasto 0.9amps - a win to Eberspacher
Lowest Fuel Consumption:
Eberspacher 0.10 litres per hour on low, Webasto 0.12 litres per hour on low - another win to Eberspacher
Both are great heaters and you will fundamentally happy with the warmth either will supply. But the Eberspacher ticks more boxes. We see the Webasto installed into manufacturers of caravans and motor-homes who seem to be very focused on price reduction from their suppliers, IE it is a cheaper heater. Again I stress both are good heaters and should make you happy - but my recommendation is the Eberspacher or a heater similarly constructed to the Eberspacher like the Warmda. Be wary of all clones of the Webasto as they do not work anywhere as well as the original (and as shown the Webasto is not the winner, so these heaters are a even lower choice).
All Warmda heaters are based/similar to the Eberspacher - with some features that make them an even better option:
- 5 Speeds/Heat settings - even finer temperature control
- Countdown timer control as standard.
- Choice on the supplied controller as to whether you want full auto function (digitally set temperature control) or you can manually set the fan speed/heat setting you require.
- Supplied with air intake filter and silencer as standard.
- Even lower power and fuel consumption compared to Eberspacher.
Simply put, Warmda is the best value air heater on the market.