The kind of device you'll want really depends on your needs: how
large of an area you wish to heat and how much, and what type of power
you want to use and portability, if any.
- Power source. You can get patio heaters
that are powered by propane, natural gas or electricity. Propane
will be the most expensive fuel, but it is portable. The price advantage between
natural gas and electricity can vary from year to year and by locale. For
a natural gas heater, you'll
need a natural gas line installed by someone qualified to do that
work. Some electric heaters can plug into an electric outlet, but some need
to be directly wired. Again, that job needs to be handled by someone with
expertise.
- Heat
capacity. Tabletop models meant to heat a small area usually have
a maximum of 20,000 BTU. The standup heaters that are seven or eight feet
tall can heat up to a 20-foot radius (though most say ten feet is
more realistic) and usually have a maximum output of 40,000 BTU. Manufacturers
and retailers of electric heaters usually detail capacity in terms of watts.
While manufacturers say a patio heater can warm an area by, say, 20 degrees,
that would be in optimal conditions and only when you are close to the heater.
- Reflector size. The size of the dome-like reflector atop gas patio heaters is proportional
to the area it will heat – the larger the reflector,
the farther it will radiate. While retail websites give the size
of the reflector, they also give a range of heating distances that tells
you what you need to know without having to worry about translating dome
size to heating area.
- Safety features. Just about all patio heaters have an automatic
burner shutoff if the heater is tilted more than slightly,
and most good patio heaters also will automatically shut off the flow of gas
if the burner goes out. Some gas heaters also have an oxygen-depletion
sensor that will shut off the heater if it detects a lack of oxygen
in the immediate area. This is important if you are restricting airflow, such
as having walls to block the wind.
- Finish. Stainless steel will be more expensive than
powder-coated aluminum but will last longer. Buying a cover or
upgraded cover will protect the heater when not in use and also may prevent
insects from building a nest in the heater.
- Ignition. Most good patio heaters have
a pushbutton Piezo electric igniter, which is safer
and easier than lighting gas with a match.
- Warranty. An average residential patio heater
will have a one-year warranty, but some models have a two-year
warranty and in rare cases even more. Generally on the same model, the length
of the warranty will be shorter if you are using the heater in a commercial
situation.
Commercial-grade patio heaters obviously are
built to withstand more constant use than a residential model and usually
cost more. If you are going to be using the heater for many hours each day,
you might want to consider a commercial heater.