Technology changes every time as humans try to solve the problem. In winter, people need device to keep them warm in room and home. That kind of device has created since long time ago from traditional mode into recent advanced specification. In ancient time, people relied on wood as source of heat. They burned wood into fireplace then let fire spread heat. You need many woods to keep warm along cold weather. For harsh winter, wood is not good to keep temperature in normal level. New source came to replace wood. Moreover, charcoal is the next source of heat that has many advantages compared to wood. Unfortunately, charcoal left much dirt and exhausts much smoke.
Modern device to keep room warm is called boiler or furnace more at furnacetrend.com. In general, both of them are similar device with capability to produce heat to raise room temperature. People do not use wood anymore as the result of ecological damage. Charcoal is still optional to heat the room because it creates excessive air pollution. Modern boiler uses electric, gas, and refrigeration cycle to keep the room on stable temperature. Natural gas is cheaper and easy to find in any place. Using electricity might take much cost as the result of sensitive equipment. On the other side, refrigeration cycle is the most effective way to keep normal temperature, but it is not quite efficient.
On the market, heaters or boilers are available from many manufacturers. If you are new in this field, pick one of Goodman product. GMH80804BN uses gas as source of heating. Manufacturer puts two-stage mode on this device specification. This mode is better than single because you can control the air velocity. For residential installation, single mode produces very annoyance noise. This device is very quiet and can run in the low speed. It uses strong steel as cover with high resistant for getting rust. Therefore, your room will feel comfortable after this device is installed.