Reznor YDSA Unit Installation Manual User Manual
Page 38
Form I-Y, P/N 273646R6, Page 38
Sizing Gas Supply Lines
Capacity of Piping
Cubic Feet per Hour based on 0.3" iwc Pressure Drop
Specific Gravity for Natural Gas -- 0.6 (Natural Gas -- 1000 BTU/Cubic Ft)
Specific Gravity for Propane Gas -- 1.6 (Propane Gas -- 2550 BTU/Cubic Ft)
Length
Diameter of Pipe
of
1/2"
3/4"
1"
1-1/4"
1-1/2"
2"
Pipe
Natural Propane Natural Propane Natural Propane Natural Propane Natural Propane Natural Propane
20'
92
56
190
116
350
214
730
445
1100
671
2100
1281
30'
73
45
152
93
285
174
590
360
890
543
1650
1007
40'
63
38
130
79
245
149
500
305
760
464
1450
885
50'
56
34
115
70
215
131
440
268
670
409
1270
775
60'
50
31
105
64
195
119
400
244
610
372
1105
674
70'
46
28
96
59
180
110
370
226
560
342
1050
641
80'
43
26
90
55
170
104
350
214
530
323
990
604
90'
40
24
84
51
160
98
320
195
490
299
930
567
100'
38
23
79
48
150
92
305
186
460
281
870
531
125'
34
21
72
44
130
79
275
168
410
250
780
476
150'
31
19
64
39
120
73
250
153
380
232
710
433
175'
28
17
59
36
110
67
225
137
350
214
650
397
200'
26
16
55
34
100
61
210
128
320
195
610
372
Note: When sizing supply lines, consider possibilities of future expansion and increased requirements.
Refer to National Fuel Gas Code for additional information on line sizing.
From Gas Supply
(horizontal or vertical)
Manual
shutoff
Drip
Leg
To Gas
Valve
(inside the
cabinet)
*To Gas
Valve
(inside the
cabinet)
Ground
Joint
Union
Drip
Leg
Ground Joint Union
Manual shutoff
FIGURE 22 - Gas Connection
Depending on Model Size, refer to either
FIGURE 2 on page 7, FIGURE 3 on page
8 or
FIGURE 4 on page 9 for gas connec-
tion location.
WARNING
All components of a gas supply system must be leak tested prior to placing equipment in
service. NEVER TEST FOR LEAKS WITH AN OPEN FLAME. Failure to comply could result
in personal injury, property damage or death.
9.2.2 Checking Gas
Pressure
Inlet Pressure (See Supply Pressure Testing WARNING on previous page.)
Before attempting to measure or adjust valve outlet gas pressure, the inlet (supply)
pressure must be within the specified range both when the heater is in operation and
on standby. Incorrect inlet (supply) pressure could cause excessive outlet gas pres-
sure immediately or at some future time. If natural gas inlet (supply) pressure is too
high, install a regulator in the supply line before it reaches the heater. If natural gas
supply pressure is too low, contact your gas supplier.
Inlet pressure to the valve for natural gas must be a minimum of 5” iwc or as noted on
the rating plate and a maximum of 14” iwc
Inlet supply pressure to the valve for propane gas must be a minimum of 11” iwc and
a maximum of 14” iwc
Gas Connection Size (NOT gas supply line size)
Gas Heat Section (H=non-condensing; G=condensing heat section) Diameter
(NPT)
Single Furnace
Dual Furnaces (one gas connection)
H50, H75, H100
H102, H125, H150, H175, H202
1/2”
H200, G150
H402, G302
1/2”
H300, H400, G225, G300
H702, H802, G372, G525, G602
3/4”
9.2 Gas Heat Section (cont’d)
9.0 Optional Equipment including Heat Sections (cont’d)