- Heat up properly on board -
A warm air heating system for boats heats air from outside or from the interior of the boat via a heat exchanger and uses a powerful electric fan to circulate that hot air around the boat through ducting (diameter 60 - 100 mm). Anyone who frequently uses the hot air heating on board or lives on the boat should think about insulating hot air ducting to prevent energy loss and reduce fuel consumption. The desired temperature can be set via a control unit, e.g. in the saloon, and is regulated by a thermostat.
In heated cabins, the hot air flow is regulated via flaps on the hot air outlets. Since individual outlets can have an effect on each other and the air flow in other cabins will automatically change as soon as an outlet is closed in one cabin, diesel warm-air heaters should only be used for boats where up to three rooms are heated.
With many warm-air heaters for boats, you can choose to use circulating air or outside air, just as you can with a car. In recirculation mode, indoor air is drawn in and heated. This uses less energy to maintain the room temperature. Outside air, on the other hand, contains less moisture than the air inside the boat. Outdoor air mode thus also serves to dehumidify.
Diesel warm air heaters are installed on many boats, as the fuel needed to operate them is already on board and in sufficient quantity. Diesel is pumped out of the tank for use. Diesel hot air heaters with 2,000-3,000 watts of heating power are particularly popular and are used on 6 to 10 metre long boats. A diesel heater warms the inside of the boat very quickly to the desired temperature, keeping the interior of your boat hale and hearty. The fan is powered by the boat batteries. Fuel consumption is 0.12-0.24 litres/hour, depending on the diesel heater, and electricity consumption is 15-40 watts.
Autoterm's diesel heaters come from Russia. They are simple systems that are very easy to install. Cable harnesses are included to make installation child's play. These heaters do not often malfunction, are inexpensive and compact.
An Autoterm heater is technically similar to an Air Top heater from Webasto. Both diesel heaters have the same type of construction. The mounting flange on the underside of both heaters, where the fresh air and exhaust air ducts are connected and the diesel line is also connected, is identical. They also operate in a similar way: a fan draws in the air to be heated. Behind this there is a control board and an air-heat exchanger made of cast aluminium with an integrated combustion chamber. Inside the combustion chamber is a glow plug. The surrounding fins give off as much heat as possible to the passing air.
The differences between the two heaters are in the details. For example, the electronics of the Autoterm Air are not protected. Therefore, installation in a place with a lot of salty, humid air should be avoided. The control panel of the Autoterm Air only supports English or Russian language.
On the other hand, the cost of an Autoterm Air heater is much lower and they come with a good accessories package, which includes an extraction nozzle. This allows a canister to be converted into a diesel storage tank. The only additional item that has to be purchased is the exhaust outlet for the boat's heating system.
The Wallas Viking Air heater comes from Finland. It sets the standard in terms of quality of workmanship and possible usage options, which also includes connecting to a water pump for hot water. The control panel features a colour display and it is also possible to control your boat heating via your smartphone. The Viking features a 9 kg heating unit, to which all connections are made. The diesel pump and exhaust silencer are integrated into the aluminium housing and are completely silent. A brushless fan motor also ensures quiet operation. The smaller the boat, the more important this feature is.
The Wallas heater has two outlets for hot air. Exhaust gases escape through a wall or ceiling vent. The marine diesel heater can be controlled via an app. The control unit is wired. Power and diesel consumption is relatively high.
Purchase price is a reflection of the care taken in the workmanship, as Wallas is guided in its production by automotive standards. The Viking Air is virtually indestructible, with all components made of stainless steel and aluminium, and all plug connections made with industrial connectors.
The Webasto Air Top Heater 2000 STC comes with a cable harness for easy installation. Detailed instructions also make the Webasto warm air heater ideal for do-it-yourself installation. Stainless steel through hull flue gaskets are also included. All electronics and plug-in connections of the Webasto diesel heater are splash-proof. Purchase price is justified by good temperature control and heat output, making the heater very economical.