Whether it is for industrial, tertiary or residential installations, gas heating systems always carry the risk of leaks, the consequences of which can be catastrophic. Gas leak detectors are measuring instruments especially designed for professionals to avoid this type of accident. They make it possible to detect the slightest leak of combustible gas quickly and easily in an HVAC heating system.

What is in a modern gas detector? 

Modern gas detectors are portable and highly mobile measuring instruments. Their size and weight allow them to be held by hand, or even hung on a piece of clothing. Service technicians use portable gas detectors to locate a leak in a gas system whose tightness appears to be compromised. This applies to any type of fuel gas combustion system such as propane, methane, isobutane, LPG and other hydrocarbons. These installations can be used for heating buildings and residences, but also for furnaces, internal combustion engines, incinerators, power plants, etc. 

Different detection technologies for combustible gases 

Gas detector sensors can use several techniques to respond to the presence of a combustible gas. Each of these technologies is used in different areas depending on its specificities, qualities and drawbacks: 
 

  • Semiconductor sensors are the most commonly used by HVAC technicians. Their electrical resistance changes upon contact with a combustible gas. It is a simple and very sensitive system, which is very cost effective. However, their sensitivity can sometimes vary under certain extremes of humidity and temperature, or in the presence of high concentrations of some other, non-combustible gases.  
  • Infrared sensors are more advanced. They measure the absorption of infrared light by certain gas molecules. Their advantage lies mainly in their long life span and their near total immunity to any environmental interference: other gases, temperature, humidity, etc. However, their complexity confines them to very demanding fixed station applications in critical industrial buildings (chemical plants, energy production, furnaces, etc.). 
  • Catalytic sensors are particularly used for explosive gases. They consist of two platinum or palladium filaments (beads), one of which is insulated to serve as a witness. In the presence of a combustible gas, the other filament is subject to an oxidation reaction which raises its temperature. The temperature differential results in a voltage differential which signals the presence of a flammable gas. These sensors are fast and sensitive, but they have a limited life span and can be contaminated by certain ambient chemicals. 

Features you need in a modern gas detector 

The latest gas detectors are equipped with several features that are essential to facilitate their use and improve their efficiency: 

  • A flexible probe allows you to reach the smallest corners of a gas system. Gas ducts can run behind installations or in spaces that are very difficult to reach, and only a flexible probe can get around obstacles to get into these most unreachable corners. 
  • A sensor with very high sensitivity can detect even the smallest leaks. It must especially keep a high sensitivity for several types of combustible gases, from propane to methane, including LPG, isobutane and many hydrocarbons. 
  • A visual and audible alarm alerts the user as soon as a gas is detected. The presence of these two alarms is strongly recommended, so that the audible alarm can be heard in very brightly lit environments where the visual alarm may not be visible enough. The visual alarm allows to be noticed in a very noisy industrial environment where the sound alarm would be covered by the ambient noise. 

Combustible gas detection in HVAC systems and boilers 

The most numerous gas systems on the market are HVAC heating systems. We are talking about gas boilers, the most modern of which are condensing boilers with a very high combustion efficiency. These are present in apartments and domestic residences, but also in more powerful version in tertiary buildings, industries, and public buildings. 

These places are particularly critical for the safety of their occupants, as there can be many of them. In case of uncertainty about the tightness of the gas circuit, it is imperative that maintenance technicians go through all the pipes present to detect the slightest leak. The most sensitive installations (power plants, factories, museums, etc.) should even be equipped with stationary gas detectors in permanently monitored areas. 

Also, the detection of gas leaks allows to avoid any waste to reduce energy bills and air pollution. Â