The line of rinnai space heaters enjoys a worldwide reputation. Rinnai is a Japanese company (like so many of the leading gas technology companies) that has a firmly established presence around the globe. In fact they have subsidiaries in thirteen countries other than Japan - from China to the USA.
When it comes to propane space heaters (all of which can be fitted for natural gas), Rinnai are known for their long lasting and efficient units.
They have a specific line of energy efficient space heaters - the Energysaver range. These units are also surprisingly compact which makes them particularly suitable for out of the way parts of the home - that converted loft space for example.
These are units that avoid much of the hassle of difficult installation because these vented space heaters that do not have ducting. The bigger units are powerful and the Energysaver range can offer a whole house solution - the Rinnai RHFE-1004 can pump out almost 32 thousand British thermal units of heat an hour.
Other units include fan convectors and are vent free, which makes them great as stand-alone space heaters that can supplement other heating you have. They again run off either type of gas and are straightforward to have installed.