Caravan Diesel Heater
Caravan Diesel Heater

Diesel heating is a more cost-effective, efficient, and safe alternative to LPG heating. If you’re looking for a heating solution that’s effective and user-friendly for your vehicle, boat, or workshop. Diesel heating can also save you money. The truth is that no two of the models currently available on the market are precisely the same. Because it is based on a tried-and-true German design and is produced in a high-tech facility that has specialized in mobile heating for decades. Thermomate is head and shoulders above the competition. See below as we go through the Caravan Diesel Heater Installation.

Product Name:

THERMOMATE 12V 5kW Diesel Air Heater for Caravan Camper Trailer Van Motorhome RV.

Caravan Diesel Heater rear half

Smoothly controlling room temperature.

When you embark on your next journey, you can take the conveniences of home with you if you have a Thermomate 12V Diesel Heater with you. You can adjust the temperature from the bed using the remote control. At the same time, you set the timer on the LCD Control Panel to ensure that the cabin will be warm when you wake up and start preparing breakfast. The Thermomate will ensure that the temperature in the room is controlled smoothly and automatically while also providing continuous monitoring and diagnostics.

Because of its one-of-a-kind heatsink design, which is cast from premium 1050 grade aluminium, the Thermomate provides powerful and efficient performance. This is made possible by the heatsink’s superior thermal conductivity. Your space will be toasty in no time, regardless of whether you are in a caravan, motorhome, camper trailer, truck, or boat. Frost that on the windows will quickly melt away. The Thermometer is surprisingly quiet once the desired temperature has been reached. This means you will have satisfied campers, and everyone will have a restful night’s sleep.

Automatic cooling cycle for safety and longevity

You can run the Thermomate off the 10-litre tank, allowing up to 36 hours of operation, or you can easily connect it to a diesel fuel line already in place. The Thermometer is the most effective method for warming up parked vehicles without having to keep the engine running. When you are finished, the automatic cooling cycle will quickly bring the unit’s temperature back to normal.

Caravan Diesel Heater front half

The device can be installed quickly and without taking up much room within a vehicle’s cabin or beneath the floor. Because the Thermomate Diesel Heater comes with all of the necessary accessories already included in the package, the unit can be installed by virtually anyone handy. Put your trust in Thermomate for all your portable heating needs and make the intelligent investment in your comfort.

  1. The heatsink is made of 1050 grade aluminium, based on a tried and tested German design.
  2. Rapid heating Fully automatic control of temperature
  3. Simple to use
  4. An operation that is low in noise
  5. Auto cool down cycle LCD Control Panel or Remote operation.
  6. A compact design that facilitates straightforward assembly
  7. Included in the price are all of the necessary accessories and mounting hardware.

Installation of the Primary Heater

There must be a seal that is both secure and airtight at all times. Between the primary heater and the installation surface on the vehicle. The installation surface needs to be even, and the manufacturer’s unique gasket must be inserted. Additionally, its parts at the central heater’s installation bases should have less than one-millimetre unevenness.


After the installation holes have been drilled, the evenness needs to be improved to meet this requirement. While the component is installed, rotate each of the four M6 nuts provided until they are snug and secure. When reinstalling the primary heater, you will need to use a new gasket in place of the old one that was previously there.

After the central heater has been installed, it is essential to check to ensure that there is no contact or friction between the blade wheel of the fan. And any other nearby parts to ensure that the machine runs smoothly.

heater fuel tank and mounting plates
Heater fuel tank and mounting plates

The Installation of the System for Heating the Air

There should be no connection between the heater’s air heating system and the vehicle’s air channel. You can go with either an independent outer circulation or an inner circulation mode.

The diameter of the outer heating air tube attached to the heater should not be any smaller than 85 millimetres. The material should be able to withstand high temperatures without breaking down. There should not be more than 0.15 kPa of difference in pressure between the air inlet side of the air heating system and the air outlet side.

The hot air mustn’t come into contact with any components that are unable to withstand high temperatures. In passenger vehicles, occupants mustn’t block the hot air vent. If it is required, one can install a protective net that was provided by oneself.

Essential safety concerns

When a heater is operating in the mode known as external circulation. The positioning of the air inlet port should be such that it prevents any splashes of water or exhaust from the engine from being drawn into the heater during regular operation.

It is essential to prevent the recirculation of the supplied hot air into the air inlet port.  When the heater operates in internal circulation mode. When working in this mode, if there is no air inlet tube attached, an air inlet hood with grids must be connected to the air inlet port of the central heater. The air for the intake should be drawn from a cool part of the compartment. Like underneath the seats, for example.

Fuel Pump Installation

The fuel pump needs to be installed where there is either no residual heat from other parts of the vehicle or an abundance of cool ambient air. The temperature of the surrounding air shouldn’t be higher than 20N.

While installing the fuel pump, you will need to ensure that the pump is securely held in place by using the fuel pump holder with the heater. There is a shock-absorbing tightening piece that is used to secure the pump.

heater accessories for installation
Heater accessories for installation

Fuel Filter Installation

Before connecting the fuel line to the fuel inlet port, the fuel filter needs to be attached. Check to see that the fuel flow is being followed accurately.

Fuel Tube Installation

Only use flexible nylon tubes, which have a high resistance to light and can maintain their temperature. They are included in the package with the heater, and you can employ them to serve as the fuel tube. The tube has a diameter of 2 millimetres on the inside.

The fuel tube should be positioned to protect it from flying debris. Thus, it should be set so that it is not near any heat-emitting vehicle components. It was possible to install the fuel tube leading from the fuel pump to the central heater in any direction other than the downward direction. The fuel tube must be secured to a stable object with a tie. There is recommended less than fifty centimetres of space between the two links.


Only the connections between the fuel tube and the fuel pump, the fuel tube and the heater. The fuel tube and the sucking tube of the fuel tank. The fuel tube should be made using the fuel tube fittings that came with the heater. Clamps explicitly designed for the fuel tube should be used to ensure the fuel tube’s integrity. Eliminate all of the air bubbles that are present in the connections.

Exhaust Tube and Tube for the Installation of the Combustion Air Siphoning

Fresh air from outside the vehicle must be sucked into it to be used for combustion. The combustion exhaust must be expelled into the atmosphere via the exhaust tube. It is essential to take precautions to prevent the exhaust from getting back into the vehicle.

The tubes pass through either the vehicle’s exterior wall or holes located on the vehicle’s underside. To avoid having water get in, certain precautions need to be taken. The tubes need to be shielded and should have the capacity to withstand shocks indefinitely. Never use anything other than the air inlet tube and the exhaust tube that came with the heater. Air inlet tubes are corrugated pipes made from an aluminium tube wrapped in plastic and paper.  A tube made of corrugated stainless steel serves as the exhaust tube. Ensure that you do not confuse one with the other while the installation is done.

exhaust silencer and fuel pump
Exhaust silencer and fuel pump

Exhausts must point away from the engine

To connect them to the heater, please use the clamps to secure them firmly on the combustion air inlet and the exhaust tube vent. Only then can you join them. It is imperative that the protective hood that sits atop the ducts of the air inlet tube and the exhaust tube be maintained in a healthy state. It’s possible that removing them will cause additional damage.

If this is not the case, you should drill a hole of 4 millimetres at the bottom of the exhaust tube. To drain any water that may have condensed there. The air inlet and exhaust tubes should come out and downwards from the heater. If the pipe needs to curve, you should ensure that the curve’s radius is greater than 50 millimetres. The tubes for the intake and exhaust must point away from the engine. Thus, the pipes must be placed towards the back of the car. It is essential to ensure that the intake or exhaust is not hampered by debris, snow, or water.

Install the exhaust tube in a location that is further away from objects made of plastic or those with a low resistance to heat. The exhaust tube must be securely fastened. The exhaust vent should be angled downwards at an angle between 90 and 10 degrees to be perpendicular to the road’s surface. The clip should be positioned within one hundred and fifty millimetres of the exhaust tube’s terminus so that the appropriate angle range is obtained.

Manual Refuelling

Turn the rotary knob in the clockwise direction until all red LEDs light up. After that, hold the button labelled “OFF” for at least three seconds. At this point, diesel will be pumped in by hand into the tank. After that, you must press the OFF button for at least three seconds.

Adjusting the Settings on the Remote Control

While the heater is turned off, you need to hold down the Down button on the LCD panel for a few seconds. If it displays, it has successfully entered the interface to match the remote control code.

While holding the Power button, press the Confirm button on the remote control simultaneously. The words “waiting/matching” will appear on the remote control. The LCD panel and the remote control ought to be able to pair up independently. The LCD will automatically exit the code interface and display normal working parameters once the matching process has been completed successfully. If code matching is unsuccessful, the system will not revert to its normal working parameters. After several seconds, the LCD screen will leave the code-matching interface on its own. If it has not received any pairing code from the remote control.

Temperature Control

To display the current temperature when switching to automatic temperature control. Press the Up and Down buttons on the remote control. At the same time, the Temperature Control mode is selected by the remote control. The diesel volume will also be displayed if the temperature is adjusted manually.

Working Status Adjustment

The remote control allows for real-time adjustments to be made to the operating mode of the heater at any time:

Up button: Either raises the set temperature or raise the pump diesel amount to increase the heater’s output temperature. This function is only available in the manual temperature control mode.

Down button: Decreases the pump diesel amount (manual temperature control mode). Or reduces the setting temperature to lower the heater’s output temperature. This button is used when the heater is in manual temperature control mode.

The Changing of the Temperature Control Mode Description

First, hold the Up button while you are non-setting. Afterwards, press the Setting button to bring up the ‘P-x.x’ display. (xx denotes the quantity of diesel pumped) This indicates that you are entering the manual temperature control mode. The initial pump diesel amount is the maximum amount of diesel that can be dispensed from the pump given the current setting.

When you press the 2 buttons above, XX will appear on the screen. C, the automatic temperature control mode is entered. And the pump diesel amount is controlled to run between the maximum pump diesel amount and the initial pump diesel amount. The xx represents the temperature value.

The change in temperature triggers an automatic adjustment that can take place in either of two modes. Being for the amount of diesel dispensed by the pump. The automatic mode differs from the manual mode. It allows the pump diesel amount to reach the maximum value in the parameter settings. Even when the heater heat is at its highest. The pump diesel amount cannot exceed the current setting value in manual mode. It will not reach the maximum value in the parameter setting. This limitation applies even if the mode is switched to automatic mode. Since some older drivers are accustomed to specific temperatures, the heat is restricted to a narrower range of options.

Diesel Air Heater Safety


APPLICATIONS. The operation of the engine has no impact on the air heater. The following types of vehicles, each with their own unique power, make use of it. Cars of every kind, including trailers. The construction industry and heavy machinery Agricultural machinery. A boat, a ship, or a yacht Caravans.

FUNCTION. Reheat and remove frost from the glass. Caravans, driving cabs, cargo holds, and staff carriers’ interiors should be heated and kept warm.


living rooms, garages, boats used for residential purposes, people, animals, or objects. Remember not to install the heater near anything that has the potential to catch fire or melt at high temperatures.
While installing the exhaust vent, ensure that exhaust air does not find its way into the heating space. Via the ventilator, the hot air inlet, or a window. Always confirm the exhaust pipes are free of obstructions. The exhaust pipe outlet must be safe from anything that could catch fire. It is important to remember not to heat or ignite any flammable objects or substances. While the air heater is nearby.

It is imperative that the combustion-supporting air. Is not be breathed in at any point during the operation of the air heater. Make sure the air inlet isn’t blocked in any way, and keep it open and free of any obstructions. If the air inlet has a filter, clean it regularly to continue functioning correctly.
The fresh air that has been recirculated is used to make up the heater air. Then it is breathed in through the air heater’s filtered section. A safety fence or other appropriate tools should be used to protect the air inlet pipe. Always make sure the channel is unblocked and open.


Installing the hot air pipe in a location that is difficult to get to would be a good idea. To reduce the risk of injury (damage) to people and property. DO NOT change or modify any of the air heater’s internal components.

DO NOT make use of replacement parts produced by other manufacturers.

Always follow the instructions and guidelines when installing something or using it. You should only use the original attachments and spare parts during installation and maintenance. DISCONTINUE USE OF THE AIR HEATER IN LOCATIONS THAT MAY CONTAIN IGNITABLE VAPORS OR DUST. When adding more fuel to the air heater, turn it OFF first.

Suppose there is a fuel leak or discharge. In that case, you should make immediate repair arrangements with a qualified professional or authorized mechanic. Don’t turn off the electric power to turn off the air heater while working on something.


The discussion that was just presented elucidates the fundamental workings of the Caravan Diesel Heater Installation. As well as its most essential characteristics. Despite this, the owner’s manual should be referred to. To guarantee that your operational knowledge is exhaustive.