Camus Hydronics DFH/W500, Installation, Operation And Service Manual

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2.4.2 LOCATION OF A THRUWALL VENT TERMINATION
•
The vent cap shall terminate at least 3 feet (1M) above
any forced air inlet within 10 feet (3M) horizontally.
•
The vent cap MUST NOT terminate below a forced air
intake at any distance.
•
Do not terminate the vent in a window well, stairwell,
alcove, courtyard or other recessed area. The vent cannot
terminate below grade.
•
The vent shall not terminate less than 7 feet above a
public walkway due to the normal formation of water
vapour in the combustion process.
•
The vent system shall terminate at least 3 foot (1M) above
grade, above normal snow levels and at least 7 feet
(2.15M) above grade when located adjacent to public
walkways.
•
The vent terminal shall not be installed closer than 3 feet
(1M) from an inside corner of an L-shaped structure.
•
The vent cap should have a minimum clearance of 4 feet
(1.25M) horizontally from and in no case above or below,
unless a 4-foot (1.25 m) horizontal distance is maintained
from electric meters, gas meters, regulators and relief
equipment. In all cases local codes take precedence.
•
Flue gas condensate can freeze on exterior walls or on the
vent cap. Frozen condensate on the vent cap can result in
a blocked flue condition. Some discoloration to exterior
building surfaces can be expected. Adjacent brick or
masonry surfaces should be protected with a rust resistant
sheet metal plate.
•
The THRUWALL vent cap MUST be purchased as a kit
from the factory to ensure proper operation. Locally
purchased or fabricated THRUWALL vent caps should not
be used.
2.4.3 LOCATION OF A “THRUWALL” AIR INLET CAP
•
The termination point of the THRUWALL air inlet must be
installed a minimum of 3 feet above ground level and
above normal levels of snow accumulation.
•
The point of termination for the THRUWALL combustion
air inlet cap MUST be located a minimum of 3 feet (1M)
horizontally and 12 inches (0.30M) below the point of flue
gas termination (vent cap) if it is located within a 10 foot
(3M) radius of the flue outlet.
2.4.4 LENGTH OF AIR INLET PIPE
The maximum total length of the THRUWALL or vertical roof
top combustion air inlet pipe as installed from the appliance to
the air inlet cap must not exceed (100 ft) equivalent feet
(30.5m) in length. Subtract 7 (2.13 m) to 19 feet (5.8 m) of
equivalent length depending on centreline radius for each 90°
elbow installed in the air inlet pipe system. Pressure drop in
45° elbow will be half as much.
Do not exceed limits for the combustion air inlet piping lengths.
PART 3 GAS CONNECTION
Verify that the appliance is supplied with the type gas
specified on the rating plate. Consult factory for
installations at high altitude.
3.1 GAS CONNECTION
•
Safe operation of unit requires properly sized gas
supply piping. See gas line sizing data.
•
Gas pipe size may be larger than appliance
connection.
•
Installation of a union at the appliance gas line
connection is required for ease of service and
removal of the gas train.
•
Install a manual main gas shutoff valve, outside of the
appliance gas connection as require by local codes.
•
A trap (drip leg) MUST be provided in the inlet gas
connection to the appliance.
•
Optional gas controls may require routing of bleeds
and vents to the atmosphere, outside the building
when required by local codes. required by local
codes.
•
Larger models of this appliance may be supplied with
a gas pressure relief valve. This valve is designed to
relieve lockup pressure in excess of the high gas
pressure switch setting. It must be piped to discharge
excess gas pressure through the valve to a safe
location in accordance with local codes. Follow table
6 for sizing the vent line.
Table 5: Gas Pressure Relief Valve – Vent Manifold
Sizing Chart
Size of Combined Vent Line (Sch. 40
pipe)*
Qty. of Pressure
Relief Valves
being combined
Pressure Relief
Valve Size - 3/4"
NPT
Pressure Relief
Valve Size - 1"
NPT
1 3/4" 1"
2 1" 1 1/4"
3 1 1/4" 1 1/2"
4 1 1/4" 2"
5 1 1/2" 2"
6 1 1/2" 2"
7 2" 2 1/2"
8 2" 2 1/2"
*Up to 50 feet. Increase by one pipe size for every 50 feet
or part thereof that the vent line extends beyond the initial
50 feet. The increase is to be made at the connection to
the relief valve.