6
Table 1A First Stage Piping at High Pressure_10 PSI
The gas piping must be sized for the proper flow and length of
pipe, to avoid excessive pressure drop. Both the gas meter and
the gas regulator must be properly sized for the total gas load.
If you experience a pressure drop greater than 1 inch w.c.
(249 Pa), the meter, regulator, or gas line is undersized or in
need of service. Perform the steps below when checking inlet
gas supply:
1. Turn the main power switch to the “OFF” position.
2. Shut off gas supply at the manual gas valve in the gas
piping to the appliance.
3. Remove the 1/8" pipe plug on the flange to the factory
supplied gas shutoff valve and install a suitable 1/8"
fitting (field supplied) for the manometer tubing. Place the
tubing of the manometer over the tap once the 1/8"
fitting is installed as shown in FIG.’s 1-1 and 1-2.
4. Slowly turn on the gas supply at the factory installed
manual gas valve.
5. Turn the power switch to the “ON” position.
6. Adjust the temperature set point on the control panel of
the SMART TOUCH control module to call for heat or
utilize Service Mode, see page 10 of this manual.
7. Observe the gas supply pressure as the burner fires at
100% of rated input. Percent of burner input will be
displayed on the Modulation Screen.
8. Ensure inlet pressure is within specified range.
Minimum and maximum gas supply pressures are
specified in this section of the manual.
9. If gas supply pressure is within normal range and no
adjustments are needed, proceed on to Step 11.
10. If the gas pressure is out of range, contact the gas utility,
gas supplier, qualified installer or service agency to
determine the necessary steps to provide proper gas
pressure to the control.
11. Turn the power switch to the “OFF” position.
12. Shut off the gas supply at the manual gas valve in the gas
piping to the appliance.
13. Remove the manometer from the pressure tap on top of
the gas valve. Remove the 1/8" (3 mm) field supplied
fitting and reinstall the pipe plug removed in Step 3.
DO NOT adjust or attempt to measure gas
valve outlet pressure. Attempting to alter
or measure the gas valve outlet pressure
could result in damage to the valve, causing
potential severe personal injury, death, or
substantial property damage.
WARNING
Check inlet gas supply
1
Gas connections
Dual Fuel Supplemental Manual
The Dual Fuel Crest is equipped with
two (2) inlet gas connections. Each
connection must be checked to ensure
proper operation.
NOTICE
Table 1B Second Stage Piping at Low Pressure_1/2 PSI
10
20
30
40
50
60
70
80
90
100
125
150
1/2
2442
1885
1580
1382
1240
1133
1048
979
921
872
775
703
Pipe
3/4
4831
3812
3230
2842
2561
2346
2175
2035
1917
1816
1618
1470
Size
1
8531
6916
5939
5270
4776
4392
4083
3829
3614
3429
3063
2789
(I.D.)
1 1/4
16626 13771 11963 10691
9736
8987
8378
7872
7443
7074
6336
5779
1 1/2
23670 19957 17510 15749 14407 13341 12470 11740 11119 10581
9501
8682
2
42521 36514 32398 29359 27001 25104 23538 22216 21082 20097 18104 16580
Nominal Iron Pipe
Size Inches
Length of pipe or tubing, feet
Maximum Capacities of Pipe in KBTUH/Hr
Notice: Capacities show n are for Natural Gas. Please consult supplier for proper gas pipe sizing for propane.
10
20
30
40
50
60
70
80
90
100
125
150
1 1/4
2205
1496
1212
1039
913
834
771
724
677
630
567
511
Pipe
1 1/2
3307
2299
1858
1559
1417
1275
1181
1086
1023
976
866
787
Size
2
6221
4331
3465
2992
2646
2394
2205
2047
1921
1811
1606
1496
(I.D.)
2 1/2
10140 7046
5695
4778
4343
3908
3618
3329
3160
2991
2654
2412
3
17990 12510 10110 8481
7708
6936
6422
5908
5608
5309
4711
4281
4
36710 25520 20620 17300 15730 14150 13100 12050 11440 10830 9613
8736
Nominal Iron Pipe
Size Inches
Length of pipe or tubing, feet
Maximum Capacities of Pipe in KBTUH/Hr
Notice: Capacities show n are f or Natural Gas. Please consult supplier f or proper gas pipe sizing f or propane.
