How Does a Catalytic Heater Work?

These propane heaters are efficient, quiet and portable

By Brad Painting

Photo by iStockphoto.com

A catalytic heater is a portable unit that generates heat using propane. Its process is similar to that of a catalytic converter on an automobile, which causes emissions to chemically react into more air-friendly products. Although a catalytic heater works with different chemical reactants than a converter, it shares the property of generating heat without burning a fuel.

Uses

The first catalytic heaters were marketed toward campers and were small enough to hold in one hand. These heaters had a rated heat output of 3,000 BTUs, or British Thermal Units, and were intended for temporary usage inside tents. In later years, larger catalytic heaters emerged with ratings of 8,000 to 18,000 BTUs, which were intended for use in trailers, RVs and motor homes.

Parts

A catalytic heater basically consists of a propane tank, a metal grill, and mesh lined with platinum or other catalyst. A valve controls the flow of propane through the mesh, which creates heat that is absorbed and radiated by the metal grill. The metal grill convects heat and emits infrared waves, just like a standard infrared or radiant heater.

Chemical Reaction

The functioning of a catalytic heater relies on a balanced chemical reaction. Propane and oxygen react and form primarily water vapor and carbon dioxide. The catalyst is the key element which drives the reaction; it splits certain atoms off of molecules and recombines them into new ones. Because some molecules rearrange into lower-energy formations, they compensate by releasing heat.

Advantages

Catalytic heaters are extremely portable; you can use them in most types of enclosures or even place one outside beside yourself when camping. Because they do not rely on a combustion process, they require no gas line or flue. You can simply attach the fuel tank directly to the device and crack open a window for ventilation. They have no motorized parts so they are also quiet and reliable.

Safety

The U.S. Consumer Product Safety Commission (CPSC) analyzed the emissions from two commercial catalytic heaters in 2003. They found that while the amount of carbon monoxide released was small, the heaters' consumption of oxygen could potentially cause hypoxia (suffocation from lack of oxygen) in an airtight space. Therefore, you should only use catalytic heaters in ventilated spaces.