Outdoor Electric Heating

We believe that an electric outdoor (patio) heater is a much better choice than a gas heater.

All types of outdoor heaters generate infrared energy which is absorbed by people and experienced as heat.  Unfortunately, even the most efficient electric patio heater such as the BN Thermic HWP2 cannot claim to be 100% efficient.  We estimate that the HWP2 patio heater converts about 92% of the electricity it consumes into useful radiant energy.  The comparative efficiency of an outdoor gas heater is around 30%.

Taking into account the different levels of efficiency and the relative costs of electricity and propane gas, we calculate that the running costs of a patio heater such as our HWP2 is approximately 1/3 that of the equivalent gas heater.

With electric outdoor heaters, there is no need to organise gas cylinder deliveries or to provide a safe storage area.  You can also be certain that your electricity supply will not fail on the busiest day of the year whereas it is quite likely that a gas cylinder will run out at the most inconvenient time!

Yes – electric patio heaters are perfectly safe to be installed, operated, and left outdoors all year round.  However you should take the following precautions.

Only install an electric heater with an IP (ingress protection) rating of IP55 or higher.  This rating will ensure that water cannot penetrate the electrical connection enclosure.

Only buy an outdoor heater from a reputable manufacturer

Arrange for the installation to be carried out by a qualified and experienced professional who will understand the necessity of maintain the IP rating.

To be effective in an outdoor environment, a patio heater must emit shortwave energy which cannot be blown off course by draughts and breezes.  Shortwave energy requires a very high temperature heat emitter that can only be provided by a genuine halogen lamp.

Other heating technologies can be found on the market, such as carbon elements and ceramic plaques, but these are not ideal for outdoor heating throughout the year.

The first generation of electric outdoor heaters were adapted from floodlights and had a sheet of glass in front of the halogen lamp.  Later models, such as the BN Thermic HWP2 patio heaters, have tended to use an open-front design providing a 25% increase in heating efficiency and a staggering five-fold increase in lamp life.   This change has also allowed our designer to produce a sleeker, more modern looking and lighter weight outdoor heater.

We would definitely suggest avoiding glass-fronted patio heaters.

BN Thermic patio heaters use a halogen filled quartz lamp to generate shortwave energy.   This energy is focused by a precision engineered, highly polished reflector and passes through the air with virtually no loss in intensity until it is absorbed by a person and experienced as heat.

The following explanation of how a halogen lamp works may be of interest to the technically minded.

To produce shortwave energy a very high temperature is required.  This is achieved by centering a tungsten filament in a quartz tube.  The tungsten filament operates at an extremely high temperature and, without the presence of halogen gas, particles from the filament would evaporate and be deposited on the relatively cool inner wall of the quartz tube.  This would cause blackening and severely reduce lamp life.

The presence of halogen gas gives rise to a phenomenon known as the halogen cycle.  A chemical reaction between the halogen gas, tungsten and oxygen, creates tungsten oxyhalide molecules which, in vapour form, migrate from the inner wall of the quartz tube back towards the filament where the high temperature breaks the tungsten oxyhalide molecules apart.  At this stage, the tungsten atoms are re-deposited on the filament whilst the oxygen and halogen atoms move back towards the wall of the lamp allowing the cycle to be repeated.

The halogen cycle allows a lamp to operate at high temperature without blackening for several thousand hours.

Elsewhere in the FAQs, we have explained why we always recommend outdoor heaters that use a genuine shortwave halogen lamp such as the BN Thermic HWP2 patio heaters.  With this style of heating, some light output is inevitable and sometimes desirable as it can provide a psychological suggestion of warmth.  However, when it is important to keep light output to an absolute minimum, we recommend selecting a patio heater using BN Thermic’s Magic Lamp technology.  Magic Lamp heaters emit a soft pink glow with zero glare and are popular for installation above dining areas.

It is very easy to estimate the running costs of an electric outdoor heater by simply multiplying the output of the heater by your electricity tariff

A typical outdoor table for two would probably require a 1.5kW patio heater.  Assuming an electricity tariff of 15p/kWh the running cost per hour would be 22.5p per hour (1.5kW x 15p/kWh)

Yes – electric patio heaters are ideal for installation under a canopy or in a gazebo.

Yes – patio heaters are frequently used indoors.  They are particularly suited to rooms that are used intermittently such as sunrooms and workshops as they are instantly effective.

When a patio heater is installed at the recommended height (2m to 2.5m), there is absolutely no safety concern when heating an area of wooden decking.

For most patio heater installations, control is limited to switching heaters on and off as required.  However, this approach can lead to unoccupied areas being heated which is clearly wasteful.  The easiest way to overcome this problem is to install a push-button timer such as the BN Thermic TS-7.  This device is designed for outdoor use and can be programmed for a time delay between 5 and 90 minutes.  Once the programmed period has elapsed the patio heater will be automatically switched off.