Roberts Gorden CTCU 15 User Manual

11

When installed as a room sealed heater, the air for 
combustion is drawn in from outside the building. It 
is important to ensure that there is adequate 
ventilation to provide air for the distribution fan.

It is important to ensure that there is adequate air 
supply at all times for both combustion and heating 
requirements in accordance with local and national 
codes. 
7.2.1 Heaters Installed Within the Heated Space

Where the volume of the heated space is greater 
than 4.7 m

3

 per kilowatt of total rated heat input and 

the air change rate is at least 0.5/h, additional high 
and low level ventilation will not be required.
For a building having an air change rate less than 
0.5/h, ventilation will be necessary in accordance 
with local and national codes. Ventilation direct to 
outside must be provided as follows:

• Heaters up to 70 kW heat input 5.0 cm

2

 per kW 

of rated heat input

Where ventilation is required, air must be taken from 
an outside point where it is not likely to be 
contaminated or obstructed.
Where natural ventilation is used, suitable ventilation 
with outside air at low level must be provided in 
accordance with Section 7.2.1 and local and national 
codes.
Where mechanical ventilation is used, extract rate
must be 5% - 10% less than the inlet rate. The
mechanical ventilation must be interlocked with the
burner on the CTCU heater.