Raypak RAYTHERM 133, Installation & Operating Instructions Manual

Page: 21 / 52

21
Gas Pressure Regulator
The gas pressure regulator located in the gas valve is
preset nominally at 4" WC for natural gas, and 11" WC
for propane. Between the gas valve and the burners is
a 1/8" pipe plug. The pressure at this point, taken with
a manometer, should be about 3.7" WC natural gas
and 10.5" WC propane. Models 0181, 0261, 0331, and
0401 should be 3.9 WC natural gas. If an adjustment
is needed, turn adjustment screw clockwise to
increase pressure, or counter-clockwise to decrease
pressure.
Venting of Diaphragm Gas
Components
Gas train components that have diaphragms 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 Code. Under NO
circumstances shall bleed lines terminate in the gas
utilization equipment flue or exhaust system. Care
should be used to prevent obstruction to the bleed
lines, as blocked lines could prevent gas valves or
other devices from operating.
Fig. 20: Bleed Line Connection
N P N P N P N P N P N P N P N P N P
0133 15 35 60 145 200 500
*0182/ 0181
- 15 30 65 95 250 400 - - - - - - - - - - -
*0260/ 0261
- 10 20 40 60 140 250 560 - - - - - - - - -
*0330/ 0331
- 15 25 35 85 150 380 360 - - - - - - - - -
*0400/ 0401
- - 15 25 60 100 260 250 - - - - - - - - -
0 0 5 0 6 3 0 3 1 0 5 1 5 6 5 3 5 1 0 1 - 4 1 5 0 - - - - - - -
0 4 3 0 5 2 5 9 0 0 1 5 4 5 2 0 1 - - 4 2 6 0 - - - - - - -
0 0 6 0 6 2 0 8 1 5 7 0 8 5 3 0 2 - - - 4 2 7 0 - - - - - -
0 0 5 0 8 4 5 8 1 0 3 1 5 5 0 6 5 2 5 1 - - - 4 2 8 0 - - - - -
0926/0962 - - - 15 20 45 45 110 150 360 400 - - - - -
1083/1125 - - - 10 15 35 35 80 120 300 300 - - - - -
1178/1223 - - - - - 25 25 60 85 220 200 - - - - -
1287/1336 - - - - - 25 20 55 75 180 170 325 560 - - -
1414/1468 - - - - - 20 15 45 65 150 165 300 500 - - -
1571/1631 - - - - - 15 15 35 50 120 125 250 400 - - -
1758/1826 - - - - - 15 10 30 40 100 100 225 340 - - -
2100 - - - - - 10 10 25 30 80 75 175 260 - - -
2500 - - - - - - - 15 20 55 55 135 160 400 600 -
3001 - - - - - - - 10 15 35 40 85 120 250 500 -
3500 - - - - - - - - 10 30 30 45 80 200 400 600
4001 - - - - - - - - 5 20 25 35 65 160 300 400
1-1/2" 3/4"
MAXIMUM EQUIVALENT PIPE LENGTH
NATURAL GAS 1000 BTU/Cubic Foot .60 SPECIFIC GRAVITY @ 0.5" W.C. PRESSURE DROP
2" 2-1/2" 3" 4"
PROPANE GAS 2500 BTU/Cubic Foot 1.53 SPECIFIC GRAVITY @ 0.6" W.C. PRESSURE DROP
" 4 / 1 - 1 " 1 " 2 / 1
* Models 0181, 0261, 0331, and 0401 are Low NOx units and are not available in propane.
A minimum of 7" WC and a maximum of 10.5" WC upstream pressure under load, and no load conditions must be provided for natural gas
or a minimum of 11" WC and a maximum of 13" for propane.
Pressure drops from the no load condition to the full load condition must be no more than 30% for proper operation.
Table G: Maximum Equivalent Pipe Lengths