Gas Piping - IBC SL 20-160 G3 Installation And Operating Instructions Manual

NOTE
It is essential to check gas
supply pressure to each
boiler with a manometer or
other high-quality precision
measuring device. Pressure
should be monitored before
firing the boiler, when the
regulator is in a "lock-up"
condition and during operation,
throughout the boiler's full
modulation range.
Pay special attention to retrofit
situations where existing
regulators may have an over-
sized orifice and/or worn seats,
causing pressure "creep" and
high lock up pressures.
MODEL
SL 10-85 G3/ SL 14-115 G3 (Natural
Gas)
SL 14-115 G3, SL 10-85 G3
(Propane)
SL 20-160 G3 (Natural Gas)
SL 20-160 G3 (Propane)
SL 30-199 G3 (Natural Gas)
SL 30-199 G3 (Propane)
BOILER SYSTEMS AND OPERATION
SL 10-85 G3, SL 14-115 G3, SL 20-160 G3, SL 30-199 G3 MODULATING GAS BOILERS
Figure 41: Multiple boiler low loss header piping concept

1.7 GAS PIPING

The boiler requires an inlet gas pressure of at least 4.0" w.c. for natural gas or propane.
For either fuel, the inlet pressure shall be no greater than 14.0" w.c. Confirm this pressure
range is available with your local gas supplier.
The inlet gas connection of the boiler's gas valve is 1/2" NPT (female).
Adequate gas supply piping shall be provided with no smaller than a 1/2" Iron Pipe Size
(e.g. Iron Pipe Size (IPS) and using a 1" w.c. pressure drop, in accordance with the
following chart:
1/2" IPS
30'
90'
10'
50'
10'
30'
Table 6: Maximum Pipe Length (ft) Schedule 40 steel
3/4" IPS 1" IPS
125'
350'
70'
200'
40'
125'
1-1/4" IPS
400'
1,000'
200'
600'
150' 600'
400' 1,600'
1-31