Combustion Air Duct - Schwank STS-JZ Installation & Owner's Manual

10. COMBUSTION AIR DUCTING
Do not install filters on the combustion air intake.
Ensure adequate clearance at the burner air intake for sufficient combustion air supply.
Do not drop the level of the air intake below the level of the heater.
When tube heater is vented to the outside and operated in a negative air condition or air-born
dust or contaminants are present (woodworking, welding shops, etc) air for combustion must
be ducted from outside the negative pressure or contaminated area to the 4 inch (100 mm) di-
ameter intake flange on the blower. NOTE: 200,000 Btuh burner requires 5" [125 mm] air
duct reduced to 4" [100 mm] at the collar on the blower. Combustion air duct must be of
noncombustible material. Maximum system, vent and duct lengths are listed in Table 4 above.
The total system length and individual flue vent or the combustion air duct is not to ex-
•
ceed the lengths listed above
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 may create condensation or soot conditions 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
•
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.
CAUTION: If a tube system is indirectly vented, ensure that warm moist outside air is not
drawn through the air duct and tube system during summer months - condensation can occur
inside the system and cause damage.
Do not use flexible dryer hose or any 'soft wall' tubing for air inlet duct, the corrugated sides
of this tubing restrict air flow. A good quality industry approved insulated flex duct is allowed for
lengths up to 10 feet - ensure duct is straight or has uniform bends to minimize friction.
CAUTION:
Trichloroethylene 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 buildings. Typical sources of other contaminants are paint removers, paints,
refrigerants, solvents, adhesives, degreasers, lubricants, pesticides, etc.
The heater manufacturer cannot anticipate all types and chemical composition of
possible contaminants at project sites. Confer with project site safety, health and
engineering staff and/or local authorities having jurisdiction such as the Fire Mar-
shall and Department of Labor for possible contaminants and any conflict with the
installation of hot surface heating equipment.
In locations where chlorinated Hydrocarbons are in use, such as
21
STS-JZ-F / IQ-F I&O Manual Z83.20-2016
IM101220
RD: APR 2019
RL: 20C