For over a century, petroleum lamps have fascinated people with their bright, warm light - completely without electricity. Especially pressure lamps such as the legendary Petromax HK500 inspire outdoor enthusiasts, nostalgics and those interested in technology alike. But how does such a high-pressure lamp actually work? In this guide, we explain the technology behind petroleum lamps in an understandable way and show what makes these special light sources so powerful.
Table of contents
What is a pressure lamp?
The functional principle: How is the bright light created?
The most important components of a pressure lamp
The starting process: Preheating is crucial
Why pressure lamps shine so brightly
The Petromax HK500: A classic of the high-intensity light technology
Fuels for pressure lamps: What needs to be considered?
Maintenance and care: How to keep your pressure lamp working
Common problems and their solutions
Advantages of pressure lamps compared to other light sources
Conclusion: Fascinating technology with tradition
What is a pressure lamp?
A pressure lamp - also known as a high-pressure lamp or kerosene pressure lamp - is a special form of kerosene lamp that achieves an exceptionally high light output thanks to an ingenious pressure system. In contrast to simple kerosene lamps with a wick, pressure lamps, depending on their design, achieve light outputs that are often described with high-intensity light classes such as 120 to over 400 "watts" (historically established specification in the high-intensity light range; not to be equated 1:1 with the electrical power consumption of modern LED lamps).
The key difference lies in the operating principle: whereas in conventional kerosene lamps the fuel is sucked up by a wick, pressure lamps work with gasified kerosene that is under pressure. This system enables much more efficient combustion and therefore a much brighter light.
The operating principle: How is the bright light produced?
The way a pressurized kerosene lamp works is based on a fascinating physical principle that can be broken down into several steps:
1. pressure generation in the tank
It all starts with the fuel tank, which is filled with pure kerosene or high-quality kerosene oil. Air is pumped into the tank using an integrated hand pump. Typically, a starting pressure is built up first (e.g. approx. 1.5 bar), while after ignition the lamp is brought to operating pressure (e.g. approx. 2.5 bar). This pressure is a basic requirement for the operation of the lamp because it enables the fuel to be delivered.
2. delivery of the fuel
The built-up pressure transports the liquid kerosene from the tank upwards through a thin pipe. In this way, the fuel passes through the so-called gasifier - the heart of every pressure lamp.
3. gasification in the gasifier
In the gasifier, the liquid petroleum is converted into a gaseous state by heat. This process is crucial for the high light yield. The gasified petroleum then flows through a precisely manufactured nozzle into the mixing chamber, where it mixes with air - similar to a gas burner.
4. combustion in the mantle
The petroleum-air mixture finally reaches the mantle - a fine-meshed fabric impregnated with fluorescent salts. This is where the actual light generation takes place: The gas burns and causes the impregnation in the mantle to glow. This produces the characteristic, bright and warm light.
5. protection and optimization
The highly heat-resistant glass cylinder surrounds the mantle and fulfills several functions: It protects the sensitive combustion chamber from wind, supports a stable air flow (chimney effect) and thus contributes to even combustion. Irrespective of this, pressure lamps develop high temperatures - it is therefore essential to maintain safety distances and allow them to cool down after operation.
The most important components of a pressure lamp
To fully understand how it works, it is worth taking a look at the main components:
- Tank with hand pump: Stores the fuel and generates the necessary pressure. A pressure gauge shows the current pressure.
- Carburetor with nozzle: Converts liquid petroleum into gas. The nozzle precisely meters the fuel flow - its size determines the light output of the lamp.
- Mixing chamber: This is where the gasified kerosene is mixed with oxygen before it reaches the bulb.
- Glow mantle: The fabric impregnated with fluorescent salts is the actual "light source". The first time it is used, it must be activated by burning off.
- Burner: feeds the gas-air mixture to the mantle and holds it in position.
- Glass cylinder: Protects the combustion chamber and supports a stable air flow for even combustion.
- Control valve/hand wheel: Opens and closes the fuel supply (switching on and off). Due to the design, the light output is generally not infinitely variable.
The starting process: Preheating is crucial
A special feature of pressure lamps is the starting process. In order for the carburetor to vaporize the kerosene, it must first be brought to operating temperature. This process is called "preheating" and can be carried out in two ways:
- With rapid igniter: Many modern pressure lamps have an integrated rapid preheater. This ignites a small amount of kerosene under pressure, the flame of which heats up the carburetor.
- With methylated spir its: Alternatively, a preheating bowl can be filled with methylated spirits and ignited. This method is gentler on the glow plug and is preferred by many experts. At least two full bowls of methylated spirits should be burned in succession to ensure a sufficient preheating time of around 90 seconds.
Only when the carburetor is hot enough can the main flame be ignited. Opening the valve too early leads to incomplete carburetion - the lamp would then burn at the top instead of glowing in the glow plug.
Why pressure lamps shine so brightly
There are several reasons for the impressive light output of pressure lamps:
- Efficient combustion: gasification and the optimum mixing ratio of fuel and air result in almost complete combustion.
- Glow salts in the mantle: The chemical composition of the impregnation - typically thorium or cerium compounds - converts the combustion heat particularly efficiently into visible light.
- Constant pressure: The overpressure in the tank ensures a constant fuel supply and therefore stable light output.
- Optimized air supply: The glass cylinder creates a chimney effect that constantly supplies fresh oxygen.
The Petromax HK500: A classic of high-intensity lighting technology
The Petromax HK500 is an outstanding example of German engineering in the field of pressure lamps. This legendary high-pressure lamp, which has been in production since 1910, combines all the functional principles described above to perfection and achieves an impressive light output of over 400 watts.
The HK500 consists of more than 200 individual parts, which are still assembled by hand in German manufacturing quality. Its highly heat-resistant borosilicate glass cylinder from Schott makes it particularly weather-resistant - wind and weather cannot harm this robust light source.
What makes this lamp particularly versatile: with the appropriate accessories, it can be used not only as a light source, but also as a stove or heater. This makes it the ideal companion for outdoor adventures, camping or as reliable emergency lighting.
Fuels for pressure lamps: What needs to be considered?
Choosing the right fuel is crucial for the function and service life of a pressure lamp. In principle, pure kerosene (lamp oil) and high-quality kerosene oil such as Petromax Alkan are best suited. These fuels vaporize evenly at the right temperatures and burn almost residue-free.
Less suitable, however, are scented oils or colored oils, which often contain additives. These can clog the fine nozzle and impair the function. Petrol should also never be used - it is too volatile and poses a considerable risk of explosion. Diesel is also unsuitable as it is too viscous and produces a lot of soot.
Suitable fuels:
- Pure petroleum (lamp oil)
- High-quality kerosene oil (such as Petromax Alkan)
Unsuitable fuels:
- Scented oils or colored oils (clog the nozzle)
- Petrol (too volatile, risk of explosion)
- Diesel (soots heavily, too viscous)
The quality of the fuel has a direct influence on the brightness of the lamp, the development of soot and ultimately the service life of all components. Impurities in the fuel can clog the precisely manufactured nozzle in particular, leading to uneven combustion and reduced light output. If you want to enjoy your pressure lamp in the long term, you should therefore not save money at the wrong end and only use high-quality, pure fuels.
Maintenance and care: How to keep your pressure lamp in good working order
Although pressure lamps are designed to be extremely robust and durable, they require regular care in order to function reliably in the long term. We tell you what is important and when.
After each use:
- Release the pressure completely via the air release screw
- Allow the lamp to cool down completely
- For longer storage: Close the pressure gauge and carburetor
Check regularly:
- Check glow plug for damage and replace if necessary
- Clean the nozzle with the cleaning needle if necessary
- Check distance between nozzle and mixing tube (14.3-14.7 mm)
- Grease pump leather sleeve and replace if worn
Important safety instructions:
- Never operate in closed rooms (combustion gases!)
- Maintain sufficient distance from flammable materials
- Never refill during operation
- Only use original spare parts
Common problems and their solutions
The lamp on the upper part is lit: The carburetor has not been preheated sufficiently. Solution: Preheat for at least 90 seconds; if preheating with alcohol, use two full bowls if necessary.
The lamp flickers or becomes dimmer: Too little pressure or too little fuel. Solution: Pump up the pressure; if necessary, clear the nozzle via the mechanism (360° handwheel).
The mantle does not flame completely: During preheating, the glow plug must be completely caught by the flame. Solution: Correct the position of the new mantle.
The pump is not working properly: Leather sleeve dry/worn. Solution: Grease/spread or replace.
Advantages of pressure lamps compared to other light sources
What makes pressure lamps so attractive even today, in the age of LEDs and rechargeable battery technology? One decisive advantage is the complete independence from power sources. A pressure lamp works anywhere - in the most remote cabin, in the forest, on a boat or during a long power cut. While batteries discharge and rechargeable batteries eventually run out, a pressure lamp lights up as long as there is fuel in the tank.
The brightness is another plus point. While most battery-powered camping lamps achieve between 100 and 200 lumens, a good pressure lamp produces a light equivalent to several hundred watts. This luminosity is ideal for larger areas, social gatherings or when really bright working light is required. At the same time, the lamp also generates warmth as a pleasant side effect - a welcome bonus on cool evenings.
The special atmosphere created by a pressure lamp can hardly be put into words. The warm, lively, dancing light is fundamentally different from the cold, static light of modern LEDs. It creates a cozy atmosphere and a very special mood that many people appreciate, especially when camping or during outdoor activities. The quiet hissing of the lamp is often perceived as calming rather than disturbing.
When it comes to longevity, modern disposable products cannot keep up. With good care, a high-quality pressure lamp will work for decades - some examples have been shining reliably for over 50 years. This not only makes it a sustainable product, but often also an heirloom that is passed down from generation to generation. And if something does break, unlike modern electronic devices, pressure lamps are easy to repair. There are replacements for almost every part, and many repairs can be carried out by yourself with a little skill.
All the advantages at a glance:
- Independence: Works without electricity, perfect for remote locations, power cuts or outdoor activities.
- Brightness: Achieves light outputs that are almost impossible to achieve with battery-powered lamps.
- Warmth : Generates warmth as a pleasant side effect.
- Atmosphere: The warm, lively light creates a special atmosphere.
- Longevity: With good care, pressure lamps work for decades.
- Sustainability: Can be repaired and used for a long time with spare parts.
Conclusion: Fascinating technology with tradition
Petroleum pressure lamps are impressive examples of how sophisticated mechanics and physical principles can transform a simple concept - the combustion of petroleum - into a highly efficient light source. The combination of pressure generation, gasification and special incandescent bulb technology enables light outputs that were revolutionary 100 years ago.
Today, these lamps not only inspire as nostalgic relics, but also as reliable, independent light sources for outdoor enthusiasts, campers and anyone who values self-sufficiency. Understanding how they work not only helps with correct operation, but also with the appreciation of this tried and tested technology.
Anyone who has ever put a pressure lamp into operation and experienced its bright, warm light will understand the fascination that these technical masterpieces exude. With the right care and a little practice in handling, a high-quality pressure lamp will be a faithful companion for many years - and perhaps even generations.
Ready for your own starlight experience? Discover the Petromax kerosene lamps now and find the perfect lamp for your needs!
