Serires KMI
- 17 -
November 4, 2013
Goch GmbH & Co. KG
Ventilation
Buildings using high intensity radiant heaters require ventilation. High Intensity type heaters are
considered un-vented gas fired appliances, requiring ventilation to supply combustion air and
dilute/remove the products of combustion.
Requirements for combustion air supply and dilution air vary by jurisdiction, building type and
specific installation details.
See local codes for guidance
. In general, where heaters are
installed without direct outside combustion air, fresh air ventilation must be provided to building
space (3 cfm per 1000 BTU/Hr in Canada, 4 cfm per 1000 BTU/Hr in the USA),
Verify
applicable local codes in the USA as requirements change by jurisdiction.
Mechanical exhaust should be electrically interconnected with the heaters and should
always be installed in conjunction with inlet air openings. See “Block Diagram for
Interconnecting Fan/Humidistat” above for details.
Inlet air opening should be relatively small and distributed over the operating area of the
heaters. They must always be located below the level of the heaters. One square inch of
net free inlet area per 1000 BTUH is recommended.
Condensation
The products of combustion for natural gas contain up to 1 liter of water per 100,000 BTU
consumed. This may add substantial amounts of moisture to the building air environment and
may become a problem of condensation on cold surfaces within the building. This is particularly
true for poorly insulated metal roof decks or structural steel framing.
To decrease condensation, increase mechanical ventilation.
Ensure that continuous waterproof barriers are used on the inside of all insulated
surfaces.
Ensure that exhausters pull air from the entire space and across the condensing surface.
Humidistat controls may be integrated into the electrical control circuit of the heaters.
