Raypak RAYTHERM 0042B, Installation & Operating Instructions Manual

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3. Except for carpeted flooring, boilers are certified
for installation on combustible floors.
4. For un-insulated hot water pipes, maintain a 2"
clearance, or consult local authority having juris-
diction.
Combustion/Ventilation Air
1. The boiler must be provided with adequate supply
of air for proper combustion and ventilation in
accordance with the latest edition of the National
Fuel Gas Code, ANSI Z223.1, or applicable provi-
sions of the local building codes.
2. Models 0042 and 0066 only: When the boiler is
installed in a confined space such as a utility room
or closet where all air is supplied from inside the
building, the boiler room must be provided with
two openings, each one having a minimum net
free area, in square inches as shown in Table C.
WARNING: Air supply to the boiler room must not
be affected by mechanical exhaust vents located in
other parts of the house, such as kitchen or
bathroom fans, or attic blowers. Mechanical exhaust
vents may create a negative pressure condition in
the boiler room that can become a hazard of
asphyxiation, explosion or fire.
CAUTION: Combustion air must not be
contaminated by corrosive chemical fumes which
can damage the boiler. Measures must be taken to
prevent the entry of corrosive chemical fumes to the
combustion and ventilation air supply. Such
chemicals include, but are not limited to, chlorinated
and/or fluorinated hydrocarbons such as found in
refrigerants, aerosol propellants, drycleaning fluids,
degreasers, and paint removers. Other harmful
elements may come from bleaches, air fresheners,
or mastics. Vapors from these types of products can
form corrosive acid compounds when burned in a
gas flame. The resulting acid condensate can
damage or substantially reduce the life of the heater.
It may be necessary to provide outside air directly to
the heater in order to avoid this problem.
One opening shall be within 12" of the top, and the
other opening within 12" of the floor. If additional gas
appliances are installed in the same space, the total
input of all gas appliances installed in the same space,
must be considered in the calculation. Refer to the lat-
est edition of the National Fuel Gas Code for additional
requirements.
3. If the boiler room is located against an outside wall
and air openings can communicate directly with the
outdoors, the two openings on the outside wall must
each have a net free area as shown in Table D.
Model No. Sq. in. of Free Area
0042
0066
70
Table C: Minimum Net Free Area
NOTE: If louvers, grills or screens are used on the
openings, obtain the net free area requirements from
their supplier or manufacturer. If the design free area
of a louver is not known nor available, it shall be
assumed that wood louvers will have 20-25 percent
free area and metal louvers will have 60-75 percent
free area as specified in the National Fuel Gas Code.
Model No. Sq. in. of Free Area
0042 12
0066 18
0090 24
0135 35
0180 45
Table D: Minimum Net Free Area
Fig. 3: Location of Openings for
Combustion/Ventilation Air