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Why should I choose Webasto?

Webasto as a company have been trading for over 100 years and operate in 34 countries around the world. The company turnover is in excess of 1 Billion Pounds and they have five manufacturing facilities producing products that are used by many different industries. Their heaters can be found in many different applications including Tanks, Ambulances, Boats, Cars, Lorries, Motor homes, Caravans, Coaches, Buses and special ‘one off’ applications. Car manufacturers, such as BMW, Mercedes Benz, Land Rover, Audi, VW & Toyota, have been using their heaters as standard fitment auxiliary heating for a number of years now, chosen for their class leading efficiency and operation. We have a Worldwide Network of dealers; with nearly 200 in the UK alone, so you can always be sure of the best service and support, if you ever need it.


Will they run on Red Diesel?

This is probably the most common question asked and the short answer is yes! In fact ‘red diesel’ actually burns slightly hotter than standard white low sulphur diesel and therefore is more efficient. As with any fuel, it is the quality that matters. The main problem with red diesel, and the  inland waterways especially, is there are many different places to buy diesel from and it all depends on how it was stored, where it was bought from, how long has it been in storage, has the tank been drained and checked for water and deposit build up, how long has it been in the boats tank for and also the condition of the tanks internal surfaces. In general as long as the quality is good, there will never be a problem with running on red diesel. Webasto have been searching for ways to improve the fuel delivery to the heater to give the units the best chance possible of protection from sub standard fuels and now have a fuel filter kit available for all heaters that needs to be installed in the fuel supply line before the pump. Please see our parts and accessories section for details on price and availability.

How long is the warranty and when does it start from?

The warranty runs for two years on all Webasto heaters and this period starts from the point of sale unless the heater installation is verified by an official Webasto Dealer, then the warranty will start from the date of that inspection/installation.

We offer an installation ‘signing off service’, if required, on those units that are self installed, for £100 plus mileage. This will include a full report on the installation and a Certificate to start the warranty from the date of that inspection.

The only exception to this warranty is the burner unit and glow pin, which are consumable items, very much like filters on an engine, for example, and therefore are covered for a period of 12 months only.

What are the service intervals and costs involved?

We recommend servicing the heater once per year depending on the operation times of the unit. Generally this should be about 2,500 hours for an average use installation. If you are installing it on a ‘live aboard’ vessel, and the unit will be running more frequently/most of the time, then this figure will be around 3,000 hours. We recommend that the heater is run for at least an hour each month, even through the warmer months, to keep all internal parts in good condition. This is more critical for the Air Top heaters as they do not tend to be used during the warmer months. If you are installing a water heater version, then the system will benefit from being run with the radiator valves open to circulate the coolant around the whole boat.

 As for servicing costs, we will carry out this annual service for the nominal cost of £45 for the rest of the heaters serviceable life on all heaters supplied by us provided they are serviced on a yearly basis. If you remove the unit and send it back to us, we will service, clean, run the diagnostic report, replace any parts deemed necessary and have the unit ready for return, within 48 hours of the unit arriving with us, subject to parts availability. Alternatively, if you are passing by our base at Evesham Marina on the River Avon, we will service the heater while you wait and carry out a free visual safety check of the installation.


How easy are they to install?

The unit comes with full installation instructions and, if followed correctly, can be installed by a competent person in a day. If you do not feel like installing the unit yourself, we offer a fitting service within our local area, or we can arrange fitting of the unit to your boat if you are moored elsewhere. We also offer a complete installation service of the heating system including the calorifier(s) and radiators if required.


How do I select the right heater?

The most important answer to this is “ask for advice”! There is a formula to it, as such, and selecting the wrong unit will cause you problems in the future. The biggest mistakes we see in this area are people who have bought too small a unit for their system, and therefore found it does not generate enough heat, or too large a unit that it causes the heater to short cycle and ‘age’ prematurely.

The ‘rule of thumb’ for the calculation is, for an Air Top heater, it depends on the number of outlets required and the length of boat, and for a Thermo Top heater system, you need to calculate the total output from all your radiators throughout the boat, excluding the calorifier (in watts) and select the unit that is closest to your total wattage. Ideally, the required output will be 10% greater than the heater i.e. Thermo Top EVO unit output rated at 5kw fitted to a system requiring 5.4 - 5-6kw.

How much do they cost to run?

The day to day running costs are very low, due to the extremely efficient way in which the diesel is burnt. The Air Top units use between 0.17 and 0.60 (Air top 5500) litres per hour and the Thermo Top units between 0.29 - 0.42l/h. (Please refer to the main Webasto leaflet for specific figure for each model)


What is the delivery time?

We can usually deliver to the customer the next working day from our extensive stock of heater kits, units, accessories and spare parts. All items ordered before noon will be shipped that day for delivery the next.

Should I lag my pipe work/ducting?

For Thermo Top units this very much depends on the installation and would be advised upon after a detailed discussion or inspection on your installation, although this is not something that is standard practice.

For the Air Top range we offer a product called Thermoduct which can increase the efficiency of the system by up to 100%. Details can be found in the parts and accessories section of this website. Thermoduct will also help lower the external temperature of the air ducting by up to 70%, useful when running through lockers and storage areas.

Are there any downsides to fitting a Webasto heater?

There is only one: - You run the risk of never having the cabin space to yourself anymore as your friends and family will all want to share in the warmth and comfort on board your vessel!


Are there any other services you offer?


We certainly do! We service engines, gearbox's, heating system's, gas system's, electrical system's, BSS pre examination check/repair work, hull blacking, welding, fit-outs/re-fits, stretching work, painting, craneage, haulage, moorings, slip way, chandlery etc. etc. The best thing to do is give us call to discuss your requirements.

Thank you, see you soon.


The views and comments mentioned above are those of Webasto Marine Heating (UK), the official WEBASTO Main Dealer for Central England and are made from their extensive experience of working with Webasto heating systems. These are not republished or necessarily expressed by Webasto Product UK or any other division of the Webasto Group of companies.


If you do need to return an order, we’re happy to help. Just email us directly and we’ll take you through the process.

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