How do patio heaters work?
Patio heaters produce heat one of two ways. They either burn a fuel like propane or natural gas, or they heat an element using electricity. This heat source is then amplified through special heat directing materials so that it warms a specific area. Unlike a space heater that contains a fan, patio heaters warm the area around them by using radiant heat. The same heat that the sun produces, but without the harmful ultra-violet rays.
Every object produces radiant heat. Night vision technology works by 'seeing' that heat. A fun way to see radiant heat in our environment is to go outside in the evening of a hot day. As the sun is setting reach your palm out over the ground. Then turn you palm up towards the sky. Slowly flip your hand between the two positions. You will feel the radiant heat produced by the earth. Patio heaters are designed to produce a high quantity of radiant heat. This method of heating is much more efficient than blowing hot air into an outdoor space as that air will just escape and take the precious warmth with it. Radiant heat travels through the air and heats the objects in the patio heaters range directly.
Traditional full size patio heaters and table top patio heaters radiate heat in all directions. They range in effective heating radius from 3' to 10' (up to 20' diameter heating range). To fully take advantage of them they must be centered in the area they are heating.
Some patio heaters have been designed to heat in a specific direction. These spot heaters (often electric) are very effective as they only heat the area they are pointed towards. This allows them to be 'hidden' by mounting them on a wall or ceiling, or keeping them on the edge of the area being heated.
What fuel should I use?
Patio heaters are available with three different fuel sources, Propane, Natural Gas, and Electric. Each fuel type has its benefits:
Unparralled mobility and ease of use are the best features of propane. Propane patio heaters can be set up anywhere you can stand them. They do not need professional plumbing or installation. And the fuel tank is placed out of sight within the unit. While there is no installation costs for propane heaters, the fuel does have the highest cost of use.
Patio heaters that run on natural gas have a lower cost of operation than any other patio heaters. They have a constant supply of fuel and there is no need to worry about refilling them. However, with all natural gas appliances care must be taken when they are installed. They may need to be professionaly plumbed.
Electric patio heaters produce zero emissions themselves and have a fuel cost inbetween propane and natural gas. They may need professional installation depending on the type of voltage and wiring needed. Electric patio heaters operate efficiently, use fuel economically, and produce heat effectively.
What patio heater sizes are available?
Patio heaters are available in many sizes. The most common form factor for patio heaters is the fullsize freestanding unit operating at around 40,000 BTU's. Also available is a Table Top form factor that heats the immediate vicinity of a patio table. These smaller heaters operate at around 12,000 BTU's. Additionaly patio heaters are available as wall and ceiling mount units. The mountable patio heaters vary in size from the small 3,300 BTU units to large scale industrial units that produce hundreds of thouusands of BTU's.
Are patio heaters safe?
Patio heaters are a great way to heat your outdoor space safely. They have many safety features built in to protect your family. Most patio heaters have a tilt shut off valve. Be sure to give adequate space between the patio heater and any combustibles. Always consult your owner manual before installing your patio heater. For patio heaters between 30,000 and 50,000 BTUs, provide at least 30 inches of clearance above and on all sides of the reflector and emitter head from combustible materials. Smaller units from 10,000 to 30,000 BTUs need at least 24 inches of clearance above and on all sides of the reflector and emitter head.
How many BTU's or Watts do I need?
To determine the correct size heater for your heating needs, you will need to use the following equation: Cubic feet of area x desired temperature rise = BTU size needed.