27
A. GENERAL
1. All fuel piping to the PUREFIRE
®
boiler is to be in
accordance with local codes. In the absence of local
regulations refer to the National Fuel Gas Code, ANSI
Z223.1/NFPA 54.
2. Size and install fuel piping to provide a supply of gas
sufficient to meet the maximum demand of all
appliances supplied by the piping.
3. P
UREFIRE
®
boilers are intended for operation with
Natural Gas or Propane with sulfur content of less than
105 ppm (150 mg/m
3
) peak with an annual average of
less than 20 ppm (30 mg/m
3
). Excessive sulfur content
in fuel input can result in black deposits resembling
coffee grounds in the combustion chamber of the boiler.
B. FUEL LINE SIZING
1. The required flow rate of gas fuel to the boiler can be
determined by the following.
The gas heating value can be supplied by the gas
supplier.
2. As an alternative, use Table 5.1 to determine the
required gas flow rate which uses typical heating values
for natural gas and liquefied petroleum (LP) gas.
3. Tables 5.2 and 5.3 shows the maximum flow capacity
of several pipe sizes based on 0.3" of pressure drop.
a. The values shown are based on a gas specific
gravity of 0.60 (Typical for natural gas).
b. Multiply the capacities listed by the correction
factors listed for gas with a specific gravity other
than 0.60 to obtain the corrected capacity.
4. Size and install the fuel gas supply piping for no more
than 0.5 inches of water pressure drop between the
gas regulator and the boiler.
C. GAS SUPPLY PIPING - INSTALLATION
1. Do not install any piping directly in front of the boiler
or along either side. Always provide access to the
front cover and side panel openings.
FUEL PIPING
5. FUEL PIPING
PUREFIRE
®
Model
Required Input Rate*
Natural Gas
ft
3
/hr (m
3
/hr)
LP Gas
ft
3
/hr (m
3
/hr)
PFC-460 460 (13.0) 184 (5.2)
Table 5.1: Required Fuel Input
Pipe
Length
ft (m)
1" Pipe
1-1/4"
Pipe
1-1/2"
Pipe
2" Pipe
2-1/2"
Pipe
3" Pipe
10
(3.0)
520
(14.7)
1,050
(30)
1,600
(45)
3,050
(86)
4,800
(136)
8,500
(241)
20
(6.1)
350
(9.9)
730
(21)
1,100
(31)
2,100
(59)
3,300
(93)
5,900
(167)
30
(9.1)
285
(8.1)
590
(17)
890
(25)
1,650
(47)
2,700
(76)
4,700
(133)
40
(12.2)
245
(6.9)
500
(14)
760
(22)
1,450
(41)
2,300
(65)
4,100
(116)
50
(15.2)
215
(6.1)
440
(12)
670
(19)
1,270
(36)
2,000
(57)
3,600
(102)
60
(18.3)
195
(5.5)
400
(11)
610
(17)
1,150
(33)
1,850
(52)
3,250
(92)
70
(21.3)
180
(5.1)
370
(10)
560
(16)
1,050
(30)
1,700
(48)
3,000
(85)
80
(24.4)
170
(4.8)
350
(10)
530
(15)
930
(26)
1,500
(42)
2,600
(74)
90
(27.4)
160
(4.5)
320
(9)
490
(14)
870
(25)
1,400
(40)
2,500
(71)
100
(30.5)
150
(4.2)
305
(9)
460
(13)
710
(20)
1,130
(32)
2,000
(57)
Table 5.2: Pipe Capacity - Natural Gas:
Maximum Capacity of pipe in cubic feet per hour (cubic meters
per hour) with a pressure drop of 0.3" of water (75 Pa).
Boiler Input Rate
Gas Heating Value
Input Rate
(
ft
³
/
hr
)
=
(
Btu
/
hr
)
(
Btu
/
ft
³
)
* Natural gas input rate is based on 1,000 Btu/ft
3
, LP input rate
is based on 2,500 Btu/ft
3
.
Pipe
Length
ft (m)
1" Pipe
1-1/4"
Pipe
1-1/2"
Pipe
2" Pipe
2-1/2"
Pipe
3" Pipe
10
(3.0)
328
(9.3)
662
(18.7)
1,008
(28.5)
1,922
(54.4)
3,024
(85.6)
5,355
(151.6)
20
(6.1)
221
(6.3)
460
(13.0)
693
(19.6)
1,323
(37.5)
2,079
(58.9)
3,717
(105.3)
30
(9.1)
180
(5.1)
372
(10.5)
561
(15.9)
1,040
(29.4)
1,701
(48.2)
2,961
(83.8)
40
(12.2)
155
(4.4)
315
(8.9)
479
(13.6)
914
(25.9)
1,449
(41.0)
2,583
(73.1)
50
(15.2)
136
(3.9)
277
(7.8)
422
(12.0)
800
(22.7)
1,260
(35.7)
2,268
(64.2)
60
(18.3)
123
(3.5)
252
(7.1)
384
(10.9)
725
(20.5)
1,166
(33.0)
2,048
(58.0)
70
(21.3)
114
(3.2)
233
(6.6)
353
(10.0)
662
(18.7)
1,071
(30.3)
1,890
(53.5)
80
(24.4)
107
(3.0)
221
(6.2)
334
(9.5)
586
(16.6)
945
(26.0)
1,638
(46.4)
90
(27.4)
101
(2.8)
202
(5.7)
309
(8.7)
548
(15.5)
882
(25.0)
1,575
(44.6)
100
(30.5)
95
(2.7)
192
(5.4)
290
(8.2)
447
(12.7)
712
(20.2)
1,260
(35.7)
Table 5.3: Pipe Capacity - LP Gas (1.50 Specific
Gravity)
Maximum Capacity of pipe in cubic feet per hour (cubic meters
per hour) with a pressure drop of 0.3" of water (75 Pa).
To Next Page
Loading...
