Combustion Air Duct - Schwank UHE Installation & Owner's Manual

12. COMBUSTION AIR DUCTING
An opening is located on the top surface of the burner housing for combustion air . Ensure ade-
quate clearance around this opening to allow sufficient combustion air supply to the heater.
When a tube heater is operated in a negative air condition or air-born dust or contaminants are
present as in woodworking and welding shops, air for combustion must be ducted from outside
the negative or contaminated area to the 4 inch (10 cm) diameter intake flange supplied on the
blower. Maximum vent, duct, and total system lengths are listed in the Table previous page.
A maximum of 30 feet of outside air duct is allowed on any system
•
Total combined system length is reduced by five feet for every 90° elbow installed in the
•
vent or duct and in the tube system (see above for allowable total lengths)
Exceeding the allowable lengths noted above may create condensation problems and will
•
void CSA Design Certification and product warranty.
The air intake will not be located less than:
Three feet above grade
•
Twelve inches from flue vent terminal of any heater with input up to 100,000 Btu/hr.
•
Three feet from flue vent terminal of any heater over 100,000 Btu/hr.
•
Do not install filters on the combustion air intake.
Ensure adequate clearance around the air intake to allow sufficient combustion air sup-
ply to the heater.
This heater has an optional fresh air intake duct hood for wall (JS-0532-VC) or
roof cap (JS-0530-XX) to bring combustion air to the heater from outside. Ensure
adequate clearance around the air intake to allow sufficient combustion air supply
to the heater. If drawing fresh air from outside, it is recommended that any single
wall pipe containing cold air be insulated to prevent or reduce condensation on
the pipe.
Do not use flexible dryer hose or any 'soft wall' tubing for air inlet duct, the cor-
rugated sides of this tubing restrict air flow. A good quality industry approved in-
sulated flex is allowed.
In locations where chlorinated Hydrocarbons are in use, such as Trichloroeth-
ylene or Chloroethylene Nu it is essential that combustion air be brought in
from a non-contaminated area. Burning the fumes from these gases will create
Hydrochloric acid fumes, which are detrimental to humans, equipment and build-
ings. Typical sources of other contaminants are paint removers, paints, refriger-
ants, solvents, adhesives, degreasers, lubricants, pesticides, etc.
The heater manufacturer cannot anticipate all types and chemical composition of possible con-
taminants at project sites. Confer with project site safety, health and engineering staff and/or
local authorities having jurisdiction such as the Fire Marshall and/or Department of Labor for
the nature of possible contaminants and any conflict that can arise with the installation of hot
surface heating equipment.
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UHE-F / EIH-F I&O Manual
IM100205
RD: APR 2019
RL: 02C