The first four models do have the same heating capacity 1,9 kWh (low) to 4,8 kWh (high). The fuel consumption is per 24hour: 4,8 ltr (low) and 12 ltr (high). The specifications of model ‘Atlantic’ are a higher, about 30-50% greater output. Your choice of heater will be determined often by the cut-out in your kitchen, the oven size, the position of the chimney outlet and, of course, what appeals to you.