CUH unit heaters are designed for use as Space heaters. For satisfactory performance their total output must be sufficient to overcome the area's heat loss. The average temperature rise across the unit is 20°C and thus the CUH is not recommended for "spot" heating. (Installing an undersized or single heater to try it will not produce acceptable results. If even heating is important several units spaced around the area will give optimum conditions. Fewer high capacity units will give lower installation costs at the expense of evenness of heat. In each case the heaters should be positioned against outside walls and in areas of greatest heat loss. Their airflow's should support each other creating a circular air movement, ideally the total air volume of the space should pass through the heaters about three times per hour. The addition of centrally mounted "vertical" units will reduce stratification and improve overall space heating efficiency.

Temperature control is by either an integral (CUH-TH) or remote thermostat with on/off switch (CUH-RTH). On off switching should also be carried out via the control circuit not the main isolator as it is necessary to maintain power to the fan to allow it to run on. This purges the heater of residual heat.