Series
LTA/LTX/LTXR
Page
28 Nov./21/12
Venting / Combustion Air Ducting
General Requirements
•
Refer to the
National Fuel Gas Code,
ANSI Z223.1 (NFPA 54) in the US and CAN/CGA B149.1
and B149.2
Installation Codes
in Canada, as well as all local requirements for general venting
guidance.
•
Series LTA/LTX/LTXR Infrared Heaters may be installed vented or unvented.
•
Series LTA/LTX/LTXR Infrared Heaters may be vented horizontally or vertically using
conventional venting materials.
•
If heater is to be vented horizontally, the vent from building must:
o
Be not less than seven feet above grade when located adjacent to public walkways.
o
Terminate at least three feet above any forced air inlet located within ten feet.
o
Terminate at least four feet below, four feet horizontally from or one foot above any door,
window, or gravity inlet into any building.
o
Be located at least 12" inches from any opening through which vent gases could enter a
building.
o
Extend beyond any combustible overhang.
o
Be installed at a height sufficient to prevent blockage by snow.
•
Optional outside air supply may be directed to the heater horizontally or vertically.
I
MPORTANT
-
Maximum total vent length allowed for any model heater is 30' feet.
-
Maximum total fresh air inlet duct length allowed for any model heater is 30'
feet.
-
Total of vent length plus outside air supply duct length cannot exceed 50'
feet for any heater with minimum heat exchanger length.
-
If condensation in the vent pipe or outside air supply duct is a problem,
shorten or adequately insulate the section
Note:
The above stated requirements assume a maximum of 2 elbows in the
total combination of vent and air supply duct. Subtract 5' feet of allowable
length for each elbow if 3 or more elbows are used.
Un-Vented Operation
•
Requirements for combustion air supply and dilution air vary by jurisdiction, building type and
specific installation details.
See local codes for guidance
. In general, fresh air ventilation must be
provided to the building space at
(3 cfm per 1000 BTU/Hr in Canada)
.
In The USA verify
applicable codes.
•
Optional outside air supply is not recommended for unvented heaters due to possible pressure
imbalances in the building space.
•
Ensure that minimum combustible clearances are maintained for unvented heaters. Refer to Table
2, for required clearance dimensions.
