Frequently asked questions


We understand that you have a lot of questions.

If you could not find the answer below, please contact us.


Warranty / Parts

What is the difference in quality in comparison with other cheaper brands?

The quality is not clearly visible on the product photos, the main difference is inside. LF Bros Diesel Air Heaters are using the same high-quality parts as the most expensive brands like Eberspacher – Japanese glow plugs Kyocera, thick quality aluminum heat exchangers, high-temperature resistant plastic parts, etc.

The main strength is in the electronic components. LF Bros developed its own microprocessor controlled units with multitasking and automatic checking of values from all sensors. Also, the firmware runs the cleaning procedures to avoid creating carbon deposition and therefore increases the lifetime of the unit. With the advanced overheating protection, this makes the LF Bros heaters one of the safest Diesel Air Heaters on the market.

In contrary, most of the cheap Chinese brands are using low-quality glow plugs, heat exchangers with thin walls, plastic molded parts of low quality (harmful substance will be released after being heated), half developed electronic without safety procedures and firmware full of issues and bugs. Do not get caught buying cheap copies.

To prove the quality of the product, please check the reviews of our customers.


What is the warranty?

Every Diesel Air Heater comes with one-year standard warranty coverage through Consumer Guarantee Act (CGA). Additional LF Bros – Extended Warranty (+ $164.9 exc. GST) extends your Diesel Air Heater coverage up to two years from your purchase date.

An extended warranty covers free repair or replacement of faulty parts or parts with manufacturing defects.

Standard warranty and LF Bros – Extended Warranty does not cover replacement of the parts that have been damaged by wrong installation or by not following the Instruction Manual.


Do you supply spare parts?

Yes, we hold parts physically in stock and can sell them separately, please check Parts & Accessories. Most of the parts are compatible with another brands of Diesel Air Heaters on the market.


Do you service the units?

Yes, we do service LF Bros Diesel Air Heaters in warranty period and also offer after warranty service. We are also able to service most of the Chinese diesel air heater brands.


What safety standards does this meet? I need to know for insurance purposes.

LF Bros Diesel Air Heaters have got plenty of safety sensors and procedures that protect the unit from overheating. Products are tested and certified with following certifications: CE, E9 and EAC.


Where is the product manufactured?

Products of LF Bros are manufactured in Asia. The main export goes to Russia and the Baltic countries whose climate is the best testing environment to demonstrate the high quality of parts.



How both sizes differ from each other?

We offer two lines of product that differ in the overall dimensions of the main heating unit, the diameter of the ducting and maximal heating power.

Small heater:

This smaller heating unit has overall dimensions of 342 × 117 × 144mm. Please note that with this tiny size it offers incredible 2kW of heating power. The unit is using a ducting system with 60mm diameter.

Big heater:

Larger variant recommended for serious heating applications. This bigger brother has overall dimensions 372 × 141 × 180mm of the main heating unit and is offered in 3kW and 5kW variant of maximal heating power. The unit is using a ducting system with 90mm diameter.

It’s a good idea to consider a big heater if space allows. The unit has a bigger fan that can run with slower RPM when the heater runs on lower heating mode. It allows to produce the same level of heat but with noticeable smaller noise than a small heater.


Which power is enough for me?

Each version differs in a maximal volume of hot air that can be produced in the same heating period. The heating power of each unit can be preset manually or be regulated in thermostatic mode. The unit has a temperature sensor, that allows the heater to manage fully automatic mode for maintaining the static temperature. Fully insulated spaces do not require a big heating power while an uninsulated space has a big thermal loss and therefore requires bigger heat to maintain the room temperature.

2kW (small size only)

Great for heating small spaces as cabins of cars, trucks or campervans. The unit offers regulation of heating power between 1.1kW to 2kW.

3kW (big size only)

The middle range heater with incredible heating power enough for heating standard size motorhomes, yachts or cottages with tens of cubic meters. The unit offers regulation of heating power between 1.4kW to 3kW.

5kW (big size only)

The most powerful version of heater that is not scared of serious applications as heating large caravans, buses or spaces with more rooms. The unit offers regulation of heating power between 1.4kW to 5kW.It’s a good idea to consider a bigger heating power even for smaller spaces if budget allows. For many people, it is most critical to be able to reach room temperature in the shortest possible period especially when outside temperatures drop down. The largest 5kW unit can generate for a very short period incredibly strong dry heat and therefore reach the room temperature in the shortest possible time.


Which voltage is the right for me?

All heating units are offered in two standard voltages.

12V (DC)

The common voltage system that can be found in 95% of the applications from cars, vans, small commercial trucks, motorhomes, etc.

24V (DC)

The system that is more common in big commercial trucks, long buses, and boats.

Please always ensure, that you choose the right version. If you are not sure – ask the nearest auto electrician to check the voltage of your system.


Should I use a separate diesel tank or main tank?

Depending on your preferred set-up please choose one of the options.

Connection to the main tank

The installation kit will be including one Suction Pipe for Tank.

This variant is the best for people who want to fill on petrol station just a single tank sharing fuel for both engine and Diesel Air Heater.

Independent fuel tank

The installation kit will be including one 10l Fuel Tank, that can be installed in two different vertical positions and one Aluminium Fuel Inlet. It is suitable for applications where the main fuel tank is not available (caravans, cottages), or where the main tank of the vehicle uses petrol. Even if the main diesel tank is available, installation of this setup is usually much faster then connecting to the main tank and ensures that the main diesel tank will never get empty. The tank allows a visual check of the remaining level of fuel at every time.


Which switcher will suit me best?

All LF Bros Diesel Air Heaters are compatible with any of these remote switches. Only one switcher can be used at the same time. All switchers support the fixed power mode and thermostatic mode.

Mechanical Switcher

The most basic and intuitive switcher that offers analog rotating knob and a mechanical switch for changing the power and thermostatic mode. This switcher can be screwed to the panel and is best for applications, where is necessary the most straightforward control of power or temperature. It can show the error codes as a sequence of the flashing LED.

LED Switcher

More advanced switcher that has digital knob and LED panel that shows both heating power, set temperature and also actual temperature. The switcher allows showing direct error codes for easy troubleshooting. Can be attached to the panel by a double-sided sticker.

LCD Switcher

The most advanced switcher with 3 buttons and an LCD panel that shows both heating power, set temperature and also actual temperature. The switcher allows showing direct error codes for easy troubleshooting. It also measures the altitude from the sea level – and adjusting the amount of oxygen in the burning chamber for the applications on the mountains. Can be attached to the panel by a double-sided sticker.


Why we strongly recommend using a silencer?

The exhaust silencer/muffler is not required for the full functionality of the heater, but significantly reduced the overall noise of the unit. If the heater would be used over the night on the shared campground, the silencer should be always installed to minimize the overall noise to a minimum.Depending on your preferred setup (and space for the exhaust system) please choose one of the options.

600mm Exhaust

Kit includes one 600mm long Flexible Exhaust Pipe.

600mm Exhaust with Silencer

Kit includes one 600mm long Flexible Exhaust Pipeand one Exhaust Silencer.

1,200mm Exhaust with Silencer

Kit includes two 600mm long Flexible Exhaust Pipes and one Exhaust Silencer (that is placed in the middle of the exhaust system).



Can these heaters be legally used on New Zealand roads?

This product has the CE, E9 and EAC certifications and meets all the safety standards. Products of the brand LF Bros can be legally used on New Zealand roads.


Is this heater suitable for marine applications?

Yes, we have hundreds of satisfied customers across New Zealand who uses our heaters in marine applications.


Can these be installed into the tiny house / shipping container?

Yes, this is the cheapest, most efficient and safest heating method for the off-grid solutions where there is missing connection to 230V. LF Bros Diesel Air Heaters can produce the same heating power as an average heat pump but in a 10x smaller size!


Can I use petrol/cooking oil/kerosene?

No, the unit is designed to be fed just with clean quality diesel. We do not take any responsibility for the damage caused by inappropriate fuel. The main problem of burning other fuels is a different flash point, viscosity and purity. The result can be insufficient burning and increased carbon deposition which could permanently damage the product with the danger of fire disaster.


Is it possible to run this through a power adapter 230V AC to 12V DC or solar charged battery?

Yes, please use the power supply 12V DC with guaranteed 15-20A.



What are the detailed technical parameters?

Are these heaters able to run for long periods? Can I run it overnight and sleep?

Absolutely, every heater has got its own thermo-regulation that protects it from overheating. In case you would be using the heater stationery for very long periods on low power, we strictly recommend switching at least once per week to the highest power – which cleans the carbon deposition and increases the lifetime of the heater.


Does it have a thermostat?

Yes, all switcher support fixed power mode or thermostatic mode.


Is the diesel gravity fed or pumped?

The installation kit includes a Metering Pump(controlled by the microprocessor) that feeds into the heater unit very accurate amount of the fuel.


How does the heater handle running on high altitude (high mountains)?

Unlike the other brands of Diesel Air Heaters, LF Bros uses the pressure sensors and the advanced system automatically adjusts the ratio of fuel and oxygen. LF Bros Diesel Air Heaters were successfully tested on the Tanggula Mountains (Tibet) 17,000 feet (5182 m) from the sea level. 

This functionality is available just for LED Switcher and LCD Switcher.


Does it receive fresh combustion oxygen from interior or exterior of area?

Exterior. The fumes are also going to the exterior. This is a heat exchanger that has two closed circuits and therefore the interior air is never affected.


Can I connect more remote switchers at the same time?

No, the electrical wiring loom has got one connector for the switcher. If you decide to change the switcher, you have to first turn off the unit and disconect it from the electrical power supply. All units are compatible with any of these switchers: Mechanical Switcher, LED Switcher, LCD Switcher.



Do you have one sample set up I can have a look at and see how it operates?

Absolutely, please arrange an appointment and visit our showroom in Duvauchelle / Banks Peninsula. We are happy to answer all your questions.


Can I pick it up?

Our warehouse is located in Duvauchelle / Banks Peninsula. As we are an e-store, we do not have public opening hours. Please arrange an appointment and pick-up the items directly from our warehouse.


How can I pay? Have you got any payment plans?

We accept Bank Deposit, Online Credit Card payments, PayPal, LayBuy and Afterpay. If you decide to pay at our location, we accept Cash, Visa or Mastercard.



How long will I wait?

North Island: Standard: 2-3 Business Days 

South Island: Standard: 1-2 Business Days 


Where are you shipping from?

All the parcels are shipped from Canterbury / South Island.

What courier companies do you use?

We use the service of Fastway Couriers and CourierPost.


Do you ship internationally?

Yes, we are able to ship the product to any country. Please contact us for a quotation.



Where can I find the Installation manual?

Every installation kit includes a printed version of the installation manual, a digital copy can be found here


Will this come with everything needed to set up?

We offer the complete installation kit, that contains all the required parts for the fully working installation.


Do I need a certified installer to install this or is that enough easy to install it on my own?

This product does not have to be installed by the certified installer and meet safety inspections as gas, etc. Most of our customers install the units on their own. However, we always recommend installation by an experienced technician. 

95% of problems with functionality are caused by inappropriate installation – please read the instructions manual first. 

The standard installation process requires just basic tools as a power drill, hole cutters, screwdrivers, spanners, knife, etc. however the most important is the right placement of the individual parts.

Do you install these? Who can install it for me?

Yes, we now do installation as part of our services. Please contact us for an appointment.


Can the main unit be mounted inside or under the vehicle?

Both variants are allowed. In case of exterior installation, make sure the main heater unit is in a dry covered box with no access of water. The benefit of this variant is reduced noise in the interior. To increase the efficiency, we recommend allowing recirculation of the air by the suction of the interior air (not the cold exterior air).


Can I install the heater on its side?

No, the heater has to be exactly in the vertical position with the air suction and exhaust inlets going down. Not following this instruction will cause insufficient burning, increased carbon deposition or leaking of the fuel. 

Please refer to instructions manual – Chapter: 4.2.5


How many holes do I need to cut into the floor?

If you are installing our unit into the vehicle (van, motorhome, bus, caravan), you need to cut just one hole into the floor, thanks to the Bottom Plate with Gasket, all the important inlets will go thru the floor down.


What is the small connector at the side of the heater for?

The small connector with 2-pins is just for the purpose of diagnostic and communication with the firmware in the factory. Please do not connect any 3rd party accessories into it as you are risking permanent damage of the main Control unit.




Most of the problems with the functionality of the product we are troubleshooting with our customers are caused by failed installations that do not follow the instructions given in the manual. If you are sure that your installation is done right and you are experiencing a faulty product, please contact us.