Detroit Radiant Products Company QTD Series - Manual (Page 24)

QTD Series
24
3.0 Installation • Combustion Air Requirements
Combustion air may be supplied to the heater by indoor or outdoor means.
If using combustion air intake from indoors, the required volume of the space must be a minimum of 50 ft
3
per 1000 BTU/h (4.8 m 3 /kW) unless the building is of unusually tight construction. If the building is of
unusually tight construction with air infiltration rates of less than 0.40 air changes per hour, outside
combustion air is typically needed unless the sheer size of the building allows otherwise. Contact the
factory for further determination of air infiltration rates.
Non-contaminated outside air for combustion must be ducted to the heater if any of the following apply:
• Chemicals such as chlorinated or fluorinated hydrocarbons (typical sources are refrigerants, solvents,
adhesives, degreasers, paints, paint removers, lubricants, pesticides, etc.).
• High humidity.
• Contaminants such as sawdust, welding smoke, etc.
• Negative building pressure.
• Unusually tight construction where there is an air infiltration rate of less the 0.40 air changes per hour.
Combustion air intake may be located on either the sidewall or roof (see figures 3.15 - 3.17).
Figure 3.15 • Optional Vertical Outside Air Supply for Single Heater Intake • Side View
Figure 3.16 • Horizontal Outside Air Supply for Single Heater Intake • Side View
Roof Intake Cap Roof
18 in. Minimum
Burner
Box
Air Inlet Connection 4” pipe
(Flexible boot and band clamps are recommended)
Wall
Air Intake Cap
4” pipe
Burner
Box
Air Inlet Connection(Flexible boot and band clamps are recommended)
Combustion Air Requirements