24
Page
-Natural Gas Supply Piping-
Maximum delivery Capacity of Cubic Feet of Gas per Hour of IPS Pipe carrying Natural Gas with 0.60 Specific Gravity
Based on Pressure Drop of 0.5" W.C.
Based on Energy Content of 1,000 BTU/Cubic ft.: The water heater requires 160 Cubic ft./hr for the T-H3J-DV /
240H, 180 Cubic ft./hr for the T-H3S-DV / 340H, and 199 Cubic ft./hr for the T-H3-DV / 540H.
-Propane (LP) Supply Piping-
Maximum Capacity of Propane (LP) Based on 11" W.C. supply pressure at a 0.5" W.C. pressure drop
Pipe Size
Length
Diameter 10'
20'
30'
40'
50'
60'
70'
80'
90'
100' 125' 150' 200'
3/4"
363
249
200
171
152
138
127
118
111
104
93
84
72
1"
684
470
377
323
286
259
239
222
208
197
174
158
135
1 1/4"
1,404 965
775
663
588
532
490
456
428
404
358
324
278
1 1/2"
2,103 1,445 1,161 993
880
798
734
683
641
605
536
486
416
2"
4,050 2,784 2,235 1,913 1,696 1,536 1,413 1,315 1,234 1,165 1,033 936
801
Unit: Cubic feet per hour
Installation
Installation Manual
Water
heater
199,000 BTU/h
Dryer
35,000 BTU/h
Gas meter
Furnace
120,000 BTU/h
Range
65,000 BTU/h
A
B
C
10' Length
1/2" Pipe size
15' Length
1/2" Pipe size
15' Length
1" Pipe size
10' Length
3/4" Pipe size
10' Length
1" Pipe size
5' Length
1-1/4" Pipe size
10' Length
3/4" Pipe size
5' Length
1-1/4" Pipe size
Gas sizing example
(Natural Gas)
Unit: kBTU per hour
Pipe Size
Length
Diameter 10'
20'
30'
40'
50'
60'
70'
80'
90'
100' 125' 150' 200'
3/4"
567
393
315
267
237
217
196
185
173
162
146
132
112
1"
1,071 732
590
504
448
409
378
346
322
307
275
252
213
1 1/4"
2,205 1,496 1,212 1,039 913
834
771
724
677
630
567
511
440
1 1/2"
3,307 2,299 1,858 1,559 1,417 1,275 1,181 1,086 1,023 976
866
787
675
2"
6,221 4,331 3,465 2,992 2,646 2,394 2,205 2,047 1,921 1,811 1,606 1,496 1,260
Based on Energy Content of 1,000 BTU/Cubic ft:
Divide each appliance's BTU/h requirement by 1,000 BTU/ft
3
to get the appliances ft
3
/h requirement.
Take into account the distance the appliance is from the gas meter, look in the above gas chart to properly size the line.
For sections of the gas line supplying gas to more than one appliance (Ex: Point A to Point B), add up the cubic ft. per hour
requirements of the appliances that are being supplied by that section, and size to the farthest appliance.
For Example: The section from A to B supplies gas to the furnace, range and dryer. Adding up the BTU/h requirements and
dividing by 1,000 yields a cubic ft. per hour requirement of 220 cubic ft. of gas per hour. The farthest appliance is the range,
which is 50 ft. away from the meter. Looking at the above chart, and under the column of 50 ft., Section A to B needs to be 1"
in order to supply 220 cubic ft.
Size the gas pipe appropriately to supply the necessary volume of gas required for the water heater
using CSA B149.1, Natural gas and propane installation code or local codes.
