Rinnai M Series, Инструкция по установке и эксплуатации

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46 Rinnai M - Series Condensing Boiler Combi Manual
The gas supply must be capable of handling the entire
gas load required at the location. Gas line sizing is
based on gas type, the pressure drop in the system,
the gas pressure supplied, and gas line type. For gas
pipe sizing, refer to the National Fuel Gas Code, ANSI
Z223.1/NFPA 54, or the Natural Gas and Propane
Installation Code, CSA B149.1
For some tables, you will need to determine the cubic
feet per hour of gas required by dividing the gas input
by the heating value of the gas (available from the
local gas company). The gas input needs to include all
gas products at the location and the maximum Btu
usage at full load when all gas products are in use.
Use the table for your gas type and pipe type to find
the pipe size required. Ensure the maximum input rate
o the DHW system is used for calculating the gas pipe
sizing. The pipe size must be able to provide the
required cubic feet per hour of gas or the required
Btu/hr.
The information below is provided as an example. The
appropriate table from the applicable code must be
used.
Instructions: Enter values in empty boxes.
Rinnai Model Gas Input:
Additional Appliance Total Gas Input:
Heating Value of Gas:
Cubic Feet Per Hour (CFH):
ANSWER:
B Btu/hr
C Btu/ft
3
A Btu/hr
(CFH) =
FT
3
/HR
CFH
=
A + B
(CFH) =
C
GAS PIPE SIZING CALCULATION WORKSHEET
Natural Gas
Schedule 40 Metallic Pipe
Inlet Pressure: Less than 2 psi
Specific Gravity: 0.60
Information in table
obtained from NFPA 54,
ANSI Z223.1
- 2015.
Pressure Drop 0.5 in. w.c.
Nominal Pipe Size (in.)
1/2 3/4 1 1 1/4
Length in ft (meters) Capacity in Cubic Feet of Gas per Hour
10 (3) 172 360 678 1,390
20 (6) 118 247 466 957
30 (9) 95 199 374 768
40 (12) 81 170 320 657
50 (15) 72 151 284 583
60 (18) 65 137 257 528
70 (21) 60 126 237 486
80 (24) 56 117 220 452
90 (27) 52 110 207 424
100 (30) 50 104 195 400
EXAMPLE
Rinnai Model Gas Input:
Additional Appliance Total Gas
Input:
Heating Value of Gas:
Cubic Feet Per Hour (CFH):
ANSWER:
B
65,000
BTU/HR
C
1,000
BTU/FT
3
A
160,000
BTU/HR
160,000+65,000
(CFH) =
1000
225
FT
3
/HR
CFH
=
For this example, the pipe
diameter must be at least 3/4 in.
pipe size and 10 ft (3 m) in
length.
A + B
(CFH) =
C