Raypak XFyre 300A, Инструкция по установке и эксплуатации

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Termination
The vent terminal should be vertical and should termi-
nate outside the building at least 2 ft above the highest
point of the roof that is within 10 ft. The vent cap
should have a minimum clearance of 4 ft horizontally
from and in no case above or below (unless a 4 ft hori-
zontal distance is maintained) electric meters, gas
meters, regulators and relief equipment.
The distance of the vent terminal from adjacent public
walkways, adjacent buildings, open windows and
building openings must be consistent with the NFGC
(U.S.) or B149 (Canada). Vents supported only by
flashing and extending above the roof more than 5 ft
should be securely guyed or braced to withstand snow
and wind loads.
Common Venting
The NFGC does not address sizing guidelines for the
common venting of multiple Category IV heaters. This
is covered in the NFGC under “Engineered Vent Sys-
tems”. Table N provides volumes of flue products at full
fire for the calculation of appropriate vent and extrac-
tor sizing for common venting.
NOTE:
A vent adapter (field-supplied) may be re-
quired to connect the Category IV vent to the boiler.
WARNING:
Vent connectors serving any other
appliances shall not be connected into any portion of
mechanical draft systems operating under a positive
pressure. If an XFyre boiler is installed to replace an
existing boiler, the vent system MUST be verified to
be of the correct size and of Category IV AL29-4C
vent material, approved PVC/CPVC construction, or
Centrotherm™ polypropylene (in Canada, ULC-
S636 approved plastic materials must be used). If it
is NOT, it MUST be replaced.
NOTE:
For extractor sizing, typical CO
2
levels are
8.5% for natural gas and 9.5% for propane gas and
flue temperatures of less than 220°F.
NOTE: Data for 100% firing rate.
Table N: Volume of Flue Products Data
CAUTION:
A listed vent cap terminal suitable for
connection to the Cat IV vent materials, adequately
sized, must be used to evacuate the flue products
from the boilers.
Model No.
Vent Size
(inches)
Volume of Flue
Products (CFM)
300A
4
90
400A 120
500A 150
700A
6
210
850A 250
At the time of removal of an existing boiler, the follow-
ing steps shall be followed with each appliance
remaining connected to the common venting system
placed in operation, while the other appliances remain-
ing connected to the common venting system are not
in operation:
(a) Seal any unused openings in the common venting
system.
(b) Visually inspect the venting system for proper size
and horizontal pitch and make sure there is no
blockage or restriction, leakage, corrosion and
other deficiencies which could cause an unsafe
condition.
(c) Place in operation the appliance being inspected.
Follow the lighting instructions. Adjust thermostat
so appliance will operate continuously.
NOTE:
Vent and intake piping must be supported so
that the weight of the venting is not transfered to the
unit. Horizontal runs of vent and intake piping must
be supported to prevent sagging.
NOTE:
When using PVC “T” vent as termination,
insert the round stainless mesh screens provided
with the unit into the tee ends.
The minimum flue pipe diameter for conventional vent-
ing is: 4 in. (102mm) for Models 300A, 400A and 500A,
and 6 in. (152mm) for Models 700A and 850A.
The connection from the appliance vent to the stack
must be as direct as possible and shall be the same di-
ameter as the vent outlet. The horizontal breaching of
a vent must have an upward slope of not less than 1/4
inch per linear foot from the heater to the vent termi-
nal. The horizontal portions of the vent shall also be
supported for the design and weight of the material
employed to maintain clearances and to prevent physi-
cal damage or separation of joints.
NOTE:
When using Centrotherm ™
Polypropylene “T” vent termination , insert two
Centrotherm™ termination screens into the tee
ends.
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