Exhaust Fans - Lochinvar GAS HEATER FOR COMMERICAL POOL Installation And Service Manual

Installation and Service Manual
Figure 7 – Outside Combustion Air - Two Openings
2. Outside Combustion Air, Using Ducts
You can direct outside combustion air to this pool heater using
two air ducts to deliver the air to the mechanical room. Each
of the two openings must have a minimum free area of one
square inch per 2000 Btu input (11cm
Figure 8 – Outside Combustion Air Through Ducts
3. Outside Combustion Air, Using Direct Venting
With this option, you can connect combustion air vent piping
directly to the pool heater. See the information under Direct
Venting starting on page 21 for specific information regarding
this option.
4. Combustion Air from Interior Space
You can direct combustion air to this pool heater using air from
an adjoining interior space. You must provide two openings
from the mechanical room to the adjoining room.
Each of the two openings must have a net free area of one
square inch per 1000 Btu input (22cm
than 100 square inches (645cm
2 per kW).
2 per kW), but not less
2 ).
Figure 9 – Combustion Air from Interior Space
All dimensions are based on net free area in square inches.
Metal louvers or screens reduce the free area of a combustion
air opening a minimum of approximately 25%. Check with
louver manufacturers for exact net free area of louvers. Where
two openings are provided, one must be within 12" (30 cm) of
the ceiling and one must be within 12" (30 cm) of the floor of
the mechanical room. Each opening must have a minimum net
free area as specified in TABLE–C, page 12. Single openings
shall be installed within 12" (30 cm) of the ceiling.
The combustion air supply must be completely free of any
flammable vapors that may ignite or chemical fumes which
may be corrosive to the pool heater.
chemical fumes which must be avoided are fluorocarbons and
other halogenated compounds, most commonly present as
refrigerants or solvents, such as Freon, trichlorethylene,
perchlorethylene, chlorine, etc.
burned, form acids which quickly attack the heat exchanger
finned tubes, headers, flue collectors, and the vent system. The
result is improper combustion and a non-warrantable,
premature pool heater failure.

Exhaust Fans

Any fan or equipment which exhausts air from the mechanical
room may deplete the combustion air supply and/or cause a
downdraft in the venting system. Spillage of flue products
from the venting system into an occupied living space can
cause a very hazardous condition that must be immediately
corrected. If a fan is used to supply combustion air to the
mechanical room, the installer must make sure that it does not
cause drafts which could lead to nuisance operational problems
with the pool heater.
Vertical DirectAire™ and Horizontal DirectAire™ venting
systems have specific requirements for combustion air ducts
from the outside which are directly connected to the pool
heater. See the requirements for combustion air duct in the
venting section starting on page 12.
9
Common corrosive
These chemicals, when