<![CDATA[DIESELHEATERS4U.CO.UK - Blog]]>Fri, 17 Jan 2020 23:58:46 +0000Weebly<![CDATA[eberspacher or webasto]]>Sun, 24 Apr 2016 18:04:40 GMThttp://www.dieselheaters4u.co.uk/blog/eberspacher-or-webastoEBERSPACHER WEBASTO GUIDES&ADVICE
 Motorhome & Caravan Air Heaters

Upgrading your RV interior heating
Motorhome & Caravan Air Heaters. Which one is right for you?
There are very few things in this world that can surpass the pleasure of entering a nice warm RV or boat in the middle of winter, when it's bitterly cold outside. Well, maybe winning a brand new RV with six slides, that runs on water instead of diesel or petrol might be one? Considering the amount of money tied up in your RV or boat, only being able to comfortably use it in the warmer months of the year becomes a source of frustration for many folk. The alternative is to either 'tough it out' during the cooler months, with multiple layers of clothing and hope that your marriage relationship survives.

Fortunately, technology is now available to make both RV'ing off season and off the grid, much more comfortable and cosy. Previously, if you did have an alternate heating source, it usually gobbled up heaps of battery power and was very noisy. Newer electronic technology and in particular variable speed motors, means it is now possible to reduce the airflow speed of the circulating heated air, once the cabin temperature reaches the ideal temperature. The heater will now not only draw a fraction of the power consumption that older heaters required but also be whisper quiet.

How air heaters workAir for the heater's internal combustion process is drawn from an external intake pipe (usually through the floor) and passed into the heater's combustion chamber. It’s mixed with fuel (diesel or LPG) and automatically ignited to heat up the large surface area of a heat-exchanger. The combustion exhaust air is kept totally separate from the inside cabin air and blown back outside through an exhaust pipe. The heater’s internal blower motor draws cool cabin air past the heat exchanger where it’s heated and then blown back into the cabin again.

Deciding on a fuel source, LPG or Diesel?Most RV's and boats use LPG as a fuel source for cooking and water heating. If your engine uses diesel, then you have a choice of either fuel. However, those without diesel fuel in marine and RV powered engines can opt for installing a small diesel tank, to provide fuel for a diesel heater. The diesel tank can be situated between 6-10 metres away from the heater, so that gives some added flexibility in selecting a fuel storage site.

Both diesel and LPG fuels are widely used and considered safe. However, diesel is a lot harder to ignite in a worst case 'spill or leakage' situation. For this reason, diesel heaters can also be used while driving. This is a strong influencer for many in making a fuel source decision for their new cabin heater. It’s also a huge benefit in many bus conversions where the main heating for the dashboard has been removed. Ducting your heat to the dashboard is helpful for windscreen demisting not to mention driving comfort.

The main advantage of the newer LPG heaters is that they are cheaper to purchase than a diesel units. However, at this stage, they don't have variable speed motors and run at a set speed, switching on and off as required by a thermostat. The older generation LPG heaters had a huge current draw of about 10amps. The newer LPG heaters draw only a fraction of that amount at 1.5 amps. The LPG heaters are generally a lot noisier, than a diesel heater running on its mid and lowest speed, purely as a function of circulating a larger volume of heated air.

The diesel heater installation lends itself more to a DIY installation, for anyone that has some engineering skills. LPG on the other hand will require a certified LPG installer to connect the LPG connections and certify the overall gas installation design layout.

Some particularities about LPG in cold temperatures?The majority of LPG appliances sold in UK are manufactured overseas and designed to run on LP or liquid propane gas. The LPG we get is typically a 60:40 mixture of Propane and Butane. Both are hydrocarbon gases and both are a Liquefied Petroleum Gas, so the mixture of the two is still LPG.

There is no significant difference in the performance between the overseas propane appliance use and our Propane/Butane mix. So, if you were to travel to Australia with a UK BBQ, it would still work just fine in that country. The big disadvantage of having butane in the overall LPG mix though is that in colder parts of UK, if the temperature gets below about 2-3 degrees C, the butane content of the cylinder will stop vaporising and only the propane portion of the gas mix will be used. This is because propane will continue to vaporise down to a very cold -45 degrees C. Once all the propane has been used, the cylinder will be unable to produce any further vapour until the contents of the cylinder warms up and the butane turns back into a gas again.

A strong recommendation is to ensure you completely empty the contents of your LPG cylinder before refilling it. If you just top it up, you will find that what was left in the cylinder before refilling may be predominantly Butane. This situation will cause you more grief subsequently, as the butane content of the cylinder progressively increases and becomes excessive, at each refill, reaching levels higher than the recommended 60:40 mix.

Obviously the problem of the 'ambient air temperature' around your gas cylinder becomes more crucial the further south you travel, from say Auckland. For someone wanting to heat their RV in the middle of winter in the snow, the butane characteristic of the LPG mixture could be a problem and should influence the purchaser as to their heater fuel choice.

Running cost comparisons?The new technology Propex 1.9kw LPG heater uses 142grams of LPG an hour which works out between 47 - 55 cents per hour. A regular 9kg bottle of LPG used just for the heater will last 63 hours. (9,000/ 142g) A typical 9kg refill costs between $20-30

The similar sized diesel heater to compare against the LPG Propex heater mentioned above is theEberspacher D2 (2.2kw) heater which uses 0.28L of diesel per hour. To make a fair comparison with the Propex LPG unit, we have scaled the Eberspacher 2.2kw down to 1.9kw and this makes the diesel fuel consumption, 0.24 litres per hour. Based on diesel costing $1.50 per litre, running this heater for one hour would cost 36 cents. Typically, diesel fuel cost seems to be around 65-75% of the LPG cost in UK.

 Which heater is right for you..? Try this handy heater selection tool.Will you use your vehicle much during Winter?
 Yes  No

What size is your Vehicle?
 0-9m  9m +

Do you require heating while you drive?
 Yes  No

Does your vehicle have double glazed windows?
 Yes  No

What operating voltage will the heater run from?
 12V  24V


 A few notes on popular heater models.Propex HS2000 heater
Fuel type: LPG
Heat output: 1.9 kw
Cheapest heater. 12V only. Kitset with 1 outlet
1 year warranty

Propex HS2800 heater
Fuel type: LPG
Heat output: 2.8kw
12V only. Kitset with 1 outlet
1 year warranty

Truma E2400 heater
Fuel type: LPG
Heat output: 2.4kw
Quieter than the Propex. 12V only. Compact with more flexible mounting options. Kitset with 1 outlet.
1 year warranty

Eberspacher D2 heater
Fuel type: Diesel
Heat output: 2.2kw
12V or 24V. Digital controller. Kitset with 1 outlet
2 year warranty
Large network of service agents around the World

Eberspacher D4 heater
Fuel type: Diesel
Heat output: 4kw
12V or 24V (24V option is more expensive). Digital controller. Kitset with 1 outlet
2 year warranty
Large network of service agents around the World

Webasto AT2000 heater
Fuel type: Diesel
Heat output: 2kw
12V or 24V
2 year warranty
Large network of service agents around the World

Webasto EVO3900 heater
Fuel type: Diesel
Heat output: 3.9kw
12V or 24V. Ducting additionally purchased to suit installation. Controller lets you manually swith heater in low fan mode.
2 year warranty
Large network of service agents around the World

Webasto EVO5500 heater
Fuel type: Diesel
Heat output: 5.5kw
2 year warranty
Large network of service agents around the World

You can compare each heater’s technical attributes against each other in the Air Heater section. 
Compare fuel consumption, power consumption, dimensions, voltage options and much more.

Eberspacher / Espar Heater Installation- DIY Guide
Espar Airtronic D2
(All links open in a new window)
  • Espar of Michigan Tech Manuals

At the most basic level the Espar installation consists of:
  • Hooking up air intake and exhaust outside van
  • Hooking up the hot air duct inside van
  • Connecting your fuel line and pump wiring to the diesel tank
  • Hooking up your thermostat/controller
  • Connecting to power
Mounting the heaterMounted in the passenger seat base
Completed installation.  Air duct rotates too!
(Click for full sized pics)

Drilling template

No turning back now!

Heater, duct, and wiring harness in place

Underside view (with temporary caps over the intake and exhaust)
Slotted seat access panel



Blue sea fuse block

Espar Fuse block

Espar Fuse block

Blue sea fuse block

Brackets to pass fuel supply over the exhaust and driveshaft

GeorgeRas excellent bracket

Brackets with zip ties

Setting the fuel pump angle

Mounting the fuel pump

Ready for connection

Fuel pump connection to Aux fuel tap

Test assembling the fuel system in a clean work area

Missing barb

Dorman fuel tap and fuel hose.

Fuel tap in front left corner of fuel tank

GeorgeRas bracket template

Bending the aluminum plate

Cleaning up the edges

Heat shield

Passing the fuel pump power through the floor

Air intake

Air intake

Cutting the exhaust tubing

Heater fuel pump wiring

Using a nail to mark drilling holes for zip ties

Exhaust and intakeThe air intake sits nicely on GeorgeRa’s bracket detailed above.

Routing exhaust away from sliding door

Flex bracket

Exhaust under the driver’s door

Three attempts at making exhaust brackets

Muffler mounted mid-point

Completed exhaust

Flex bracket

Air intake

Air intake

Easy Start Select



Extension bundle, labeled on both ends

Scrapped the Espar harness and made my own bundle.
Changing from Celsius to Fahrenheit (or vice versa)I bought my Espar D2 kit from Heatso.com in London (with two day shipping to California).  The Heatso D2 kit was about $850 with muffler, and everything you need for a basic installation.  The only wrinkle was that the 801 controller came preset for Celsius.
To change from Celsius to Fahrenheit (or vice versa)-
1- Disconnect the power from the 801 controller
2- Hold down the up and down buttons
3- Reconnect power to the controller
6- Press the Heat button to save the setting
7- Voila!


Setting to Fahrenheit

To change the duration setting
Modes for controller with 6 presets:

Modes for controller with 8 presets:


Prepping the switch

SPDT rocker switch

Mountain the HA sensor

Notes on wiring

Switch functions

HA sensor and switch tucked out of the way


Labeling for clarity

Heater data function

Fault code 48- triggered when I plugged in power without the fuel pump connected.

Final notes
Comments and Feedback are welcome.  I may be able to answer technical questions.