The HOM – Combustion Air Damper is installed on the terminating end of your combustion air duct which according to the B149 Gas Code should be located within 1 ft above and within 2 ft. horizontally of the largest input appliance.
The following as taken from the B149 Gas Code
- 8.3.1 (d) (The duct shall) terminate within 1 ft (300 mm) above, and within 2 ft (600 mm) horizontally from, the burner level of the appliance having the largest input
- Reproduced with permission
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