Raypak raytherm p-1826 Installation & Operating Instructions Manual page 9

MANUAL
SHUTOFF
VALVE
GAS PRESSURE
TEST UPSTREAM
GAS PRESSURE
TEST AT GAS
VALVE
GAS PRESSURE TEST
AT HEATER
Fig. 6: Gas Pressure Test Points
Venting of Diaphragm Gas
Components
Heaters with gastrain components that have dia-
phragms in their construction are supplied with a bleed
line connection that must be connected to the outside
atmosphere as required by the National Fuel Gas
1"
Model
No.
N
926/962
1083/1125
1178/1223
1287/1336
1414/1468
1571/1631
1758/1826
2100
2500
3001
3500
4001
Natural Gas, 1000 BTU/FT
3
Propane Gas, 2500 BTU/FT
MANOMETER
1-1/4"
P N P N
15 20 45 45
10 15 35 35
25 25
25 20
20 15
15 15
15 10
10 10
.60 Specific Gravity @ 0.5 in. WC Pressure Drop
1.53 Specific Gravity @ 0.6 in. WC Pressure Drop
3
Table B: Maximum Equivalent Pipe Length
Code. Under NO circumstances shall bleed lines ter-
minate in the gas utilization equipment flue or exhaust
system.
Bleed Line
Connection
1-1/2" 2"
P N P
110 150 360
80 120 300
60 85 220
55 75 180
45 65 150
35 50 20
30 40 100
25 30 80
15 20 55
10 15 35
10 30
5 20
9
Fig. 7: Bleed Line Connection
2-1/2" 3"
N P N
400
300
200
170 325 560
165 300 500
125 250 400
100 225 340
75 175 260
55 135 160
40 85 120
30 45 80
25 35 65
4"
P N P
400 600
250 500
200 400 600
160 300 400