Takagi T-H2-DV Installation Manual And Owner's Manual page 18

4. Re open the manual gas valve. Check to see that there are no gas leaks. Open some of the fixtures
that use the highest flow rate to turn on the T H2 DV/T H2 OS.
5. Check the inlet gas pressure. When T H2 DV/T H2 OS is on maximum burn, the manometer should
read from 5.0" to 10.5" WC for Natural gas, from 8.0" to 14.0" WC for Liquid Propane.
Size the gas pipe appropriately to supply the necessary volume of gas required for the
T H2 DV/T H2 OS (199,000 BTU/h for both Natural Gas and Liquid Propane) using
ANSI233.1/NFPA 54 in the USA or CAN/CSA B149.1 in Canada or local codes.
Otherwise, flow capabilities and output temperatures will be limited.
1. Install a manual gas shut off valve between the T H2 DV/T H2 OS and the gas supply line.
2. When the gas connections are completed, it is necessary to perform a gas leak test either by
applying soapy water to all gas fittings and observing for bubbles or by using a gas leak detection
device.
3. Always purge the gas line of any debris and/or water before connecting to the gas inlet.
Maximum Delivery Capacity of Cubic Feet of Gas per Hour of IPS Pipe Carrying Natural Gas of 0.60 Specific Gravity
Based on Pressure Drop of 0.5" WC
Based on Energy Content of 1000 BTU/Cubic Ft.: T H2 DV/T H2 OS requires 199 Cubic Ft./hr.
Pipe Size
Inches 10' 20'
¾" 363 249
1" 684 470
1 ¼" 1,404 965
1 ½" 2,103 1,445 1,161
2" 4,050 2,784 2,235 1,913 1,696 1,536 1,413 1,315 1,234 1,165 1,033
Maximum Capacity of Propane (LP) Gas Based on 11" WC supply pressure at a 0.5" WC pressure drop
Pipe Size
Inches 10' 20'
¾" 567 393
1" 1,071 732
1 ¼" 2,205 1,496 1,212 1,039
1 ½" 3,307 2,299 1,858 1,559 1,417 1,275 1,181 1,086 1,023
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
For more information, please see the next page.
Natural Gas Supply Piping
30' 40' 50'
200 171 152
377 323 286
775 663 588
993 880
Propane (LP) Gas Supply Piping
30' 40' 50'
315 267 237
590 504 448
913
18
Length in Feet
60' 70' 80'
138 127 118
259 239 222
532 490 456
798 734 683
Length in Feet
60' 70' 80'
217 196 185
409 378 346
834 771 724
Page
Installation
Unit: Cubic Feet per Hour
90' 100' 125'
111 104 93
208 197 174
428 404 358
641 605 536
Unit: kBTU per Hour
90' 100' 125' 150'
173 162 146
322 307 275
677 630 567
976 866
150' 200'
84 72
158 135
324 278
486 416
936 801
200'
132 112
252 213
511 440
787 675
1,260