These heaters are placed outside of the unit that is being heated while the ducting hose blows in the heat. Fitted with its own thermostat the required temperature can be easily controlled. 
This heater is widely recognised as being amongst the UK's most popular indirect oil-fired heaters for use in marquees, temporary structures, the construction industry, and the horticultural & agricultural sectors.
 
Small:
72,000 btu, 46l tank, run time 18 hours
 
 
Large:
Output: 39kW (133,000 BTU/hr)
Fuel Tank: 65L (12 hour run time)
Dimensions: L1310 x W490 x H1020
Noise Level @1m: 74dBA
Fuel consumption: 3.9kg/h
110V. Transformers available here.