Max. power
The maximum power of the heater. The meaning of this parameter depends on the device type and power supply (see above). So, for most types of heaters, we are talking about the highest power output. However, for fan heaters, this parameter also includes the power of the fan motor, and the heating capabilities are somewhat more modest than the claimed maximum power (although not by much). For electric models, the maximum power also corresponds to the maximum power consumption, which determines the connection requirements: for example, for devices of 3.5 kW and more, ordinary sockets are no longer suitable, and some require not 230 V but 400 V.
However, the key point determined by the power of the heater, is the intensity of heating and the ability to effectively heat a particular room. To select the appropriate model, there are special formulas. So, if we are talking about a city apartment or a small office space with a ceiling height of about 2.5 m, then we can assume that a heating power of at least 100 W is required per 1 m² of area. For other situations, more complex methods are used, taking into account the volume of the room, the degree of thermal insulation, climate and solar heating, etc.; they can be found in special sources. Also note that for IR heaters (see "Type"), their own calculation methods are used — this is due to the specific format of work.
Heating area
The area that the device can effectively heat. This parameter directly depends on the maximum power (see above). It should be noted that the actual efficiency of the heater in most cases does not depend on the area but on the volume of the room. Thus, the heating area can only be specified for a certain ceiling height. In most cases, manufacturers mean 2.5 m — this is the standard ceiling height in city apartments. If the ceilings are much higher, the heating area must be recalculated using special formulas. In general, it is worth orienting that 1 kW is enough for 10 m². However, manufacturers may slightly overestimate the heating area data.
