Camus Hydronics DRH300, Installation, Operation And Service Manual

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9
2.1.6 LOCATION OF A ROOFTOP AIR INLET AND VENT
CAPS
•
The point of termination for the combustion air inlet cap
MUST be at least 3 feet (0.91M) below the point of flue
gas termination (vent cap) if it is located within a 5 foot
(1.5M) radius of the flue outlet. Use care to ensure that the
90° elbow assembly is properly installed on the air inlet
pipe.
•
The termination point of the combustion air inlet cap must
be installed at least 3 feet (0.91M) above the rooftop and
above normal snow levels.
•
The vent cap assembly MUST be listed by nationally
recognized agencies.
•
Combustion air supplied from outdoors must be free of
contaminants. To prevent recirculation of flue products in
to the combustion air inlet, follow all instructions in this
section.
•
Incorrect installation and/or location of the air inlet cap can
allow flue products to be drawn back into the appliance.
This can result in incomplete combustion and potentially
hazardous levels of carbon monoxide in the flue products.
This will cause operational problems with the appliance
and if left uncorrected, will lead to conditions that can
cause personal injury or death.
Figure 6: Vertical Direct Venting Configuration
2.1.7 AIR INLET DAMPER
In cold climates it is essential to provide a motorized air inlet
damper to control the supply of combustion air and prevent
nuisance condensation.
Figure 6: Air Inlet Damper Connection inside J-Box
2.1.8 MASONARY CHIMNEY INSULATIONS
Always follow local codes when venting this appliance into a
masonry chimney. A standard masonry chimney must NOT be
used to vent the products of combustion from the flue of a
condensing, positive or negative pressure appliance (Category
II or IV). If a masonry chimney is to be used, the chimney
MUST use a sealed, corrosion resistant liner system to vent
flue products from this high efficiency appliance. Sealed,
metallic, corrosion resistant liner systems (AL29-4C or
equivalent, single wall or double-wall, or flexible or rigid
metallic liners) must be rated for use with a high efficiency
condensing, positive pressure vent system. Corrosion
resistant chimney liner systems are typically made from a
high grade of corrosion resistant stainless steel such as
AL29-4C or equivalent. The corrosion resistant liner must
be properly sized and fully sealed throughout the entire
length. If the flue is contained within the masonry chimney
both the top and the bottom of the masonry chimney must
be capped and sealed to provide a dead air space around
the sealed corrosion resistant liner.
Consult with local code officials to determine code
requirements or the advisability of using a masonry
chimney with a sealed corrosion resistant liner
system.
2.1.9 VERTICAL VENTING TERMINATION
•
Follow Category II or IV vent termination and all
General instructions.
•
The vent terminal should be vertical and exhaust
outside the building at least 2 feet (0.61M) above the
highest point of the roof within a 10 foot (3.05M)
radius of the termination.
•
The vertical termination must be a minimum of 3 feet
(0.91M) above the point of exit.
•
A vertical termination less than 10 feet (3.05M) from a
parapet wall must be a minimum of 2 feet (0.61M)
higher than the parapet wall.
2.1.10 COMBINED COMBUSTION AIR INLET
The air inlet pipes from multiple appliances can be
combined to a single common connection if the common
air inlet pipe has a cross sectional area equal to or larger
than the total area of all air inlet pipes connected to the
common air inlet pipe.
Equivalent pipe diameter = Sq Root [(d
1
)
2
+ (d
2
)
2
+ (d
3
)
2
+
(d
4
)
2
+……+ (d
n
)
2
], d, pipe diameter
Example: What is equivalent pipe diameter of three
air inlet pipes, 8" (20.3 cm), 10” (25.4 cm) and 12”
(30.5 cm)
Equivalent pipe diameter = Sq Root [(8)
2
+ (10)
2
+ (12)
2
] =
Sq Root (308) = 17.5”, Select 18” (82.8 cm) diameter pipe
or larger.
The air inlet point for multiple boiler air inlets must be
provided with an exterior opening which has a free area
equal to or greater than the total area of all air inlet pipes
connected to the common air inlet. This exterior opening
for combustion air must connect directly to the outdoors.
The total length of the combined air inlet pipe must not
exceed a maximum of 100” (30.5M) equivalent feet. You
must deduct the restriction in area provided by any
screens, grills or louvers installed in the common air inlet
point. Screens, grills or louvers installed in the common air
inlet can reduce the free area of the opening from 25% to
75% based on the materials used. Calculate and
compensate accordingly for the restriction.
Vent
Air Intake
Air inlet must be 36”
min. below vent
opening
YELLOW
BLACK
BLUE
RED
24VAC, COMMON
CALL FOR HEAT
TO IGNITION
24VAC, CONST.
POWER