Installation Operating Instructions

34
FIG. 30
RECOMMENDED PIPING TO
BUILT-IN TANKLESS HEATERS
TABLE I - NATURAL GAS
Maximum Capacity of Piping in Cubic Feet of Gas Per Hour
(Based on a Pressure Drop of 0.3” Water
and 0.6 Specic Gravity)
Pipe
Length
in Feet
NOMINAL IRON PIPE SIZE IPS INCHES
¾ 1 1¼ 1½ 2 2½ 3 4
10 278 520 1050 1600 3050 4800 8500 17500
20 190 350 730 1100 2100 3300 5900 12000
30 152 285 590 890 1650 2700 4700 9700
40 130 245 500 760 1450 2300 4100 8300
50 115 215 440 670 1270 2000 3600 7400
60 105 195 400 610 1150 1850 3250 6800
70 96 180 370 560 1050 1700 3000 6200
80 90 170 350 530 990 1600 2800 5800
90 84 160 320 490 930 1500 2600 5400
100 79 150 305 460 870 1400 2500 5100
125 72 130 275 410 78 1250 2200 4500
150 64 12 250 380 710 1130 2000 4100
175 59 110 225 350 650 1050 1850 3800
200 55 100 210 320 610 980 1700 3500
TABLE II
Multipliers to be used with Table I when Pressure Drop is not 0.3”
Pressure Drop Multiplier
0.1 .577
0.2 .815
0.5 1.29
1.0 1.83
0.3 1.00
TABLE III
Multipliers to be used with Tables I and II for
Specic Gravity Other than 0.60
Specic Gravity Correction Factors
.50 1.10
.55 1.04
.60 1.00
.65 .96
.70 .93
36. OPEN GAS TRAIN CARTON(S)
CONNECT GAS TRAIN(S) TO ELBOW ON END OF
MANIFOLD(S) according to the Gas Trains on pages
90 thru 96. On those boilers with two manifolds (15
sect. and larger), two identical sets of Gas Controls are
furnished. Hence, the procedure for installing one set is
equally applicable to the second set.
PRESSURE TESTING of gas service piping must be
done before connecting to the boiler gas train. Test for
leaks by introducing, from an isolated source, air or
inert gas to the piping. Piping shall withstand 3 PSI
gage pressure for a period of not less than 10 minutes
without showing any drop in pressure.
SECTION III – INSTALLATION INSTRUCTIONS (continued)
must be mounted so that cut off point is above
marking on Lowest Permissible Water Line Plate.
f. Install Pressure Safety Relief Valve, using ttings
furnished, into 1-1/2” pipe tapping in upper corner
of End Section. DO NOT INSTALL A SHUTOFF
VALVE BETWEEN SAFETY RELIEF VALVE
AND BOILER. Safety Relief Valve must be
installed in a Vertical Position with handle up.
g. Install Boiler Drain Valve into one of unused return
tappings that has been bushed to ¾”. Drain Valve
can also be installed in return piping, preferably
in leg of tee that is located in line with return
connection on Boiler.
35. CONNECT PIPING TO BUILT-IN HEATER(S) IF
USED, see Fig. 30, top - left side of this page.