NTI FTVN - Part 8 - Gas Connections; Gas Pipe Sizing Tables; Gas Pipe Sizing; Natural Gas Pipe Sizing

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Part 1 - General Safety Information
Part 8 - Gas Connections
C. Additional Precaution for Excess Flow Valve (EFV)
If an excess ow valve (EFV) is in the gas line, check the manufacturer’s
minimum and maximum ow capacity ratings. An improperly sized
EFV will not allow for a full ow of gas to the boiler and will cause the
boiler to malfunction. See Figure 55.
D. Checking Gas Pressure at the Boiler for Proper
Operation
NOTE: Refer to Figure 56 when checking gas pressure. Loosen the
bolts before checking the gas inlet pressure.
1. The boiler and its individual shuto valve must be disconnected
from the gas supply piping system during any pressure testing of
the system at test pressures greater than ½ psi (3.5 kPa).
2. The boiler must be isolated from the gas supply piping system by
closing its individual manual shuto valve during any pressure
testing of the gas supply piping system at test pressures equal to or
less than ½ psi (3.5 kPa).
The minimum and maximum inlet gas line pressures must meet the
requirements shown in Table 21.
Natural Gas
Minimum Pressure 3.5” WC
Maximum Pressure 10.5”WC
LP Gas
Minimum Pressure 8” WC
Maximum Pressure 13”WC
Table 21 - Gas Pressure Requirements
4
2
1
Gas Inlet
1. Line pressure Test point
2. OFFSET Adjustment Screw
4. Throttle Adjustment Screw
Figure 55 - Excess Flow Valve (EFV)
Figure 56 - Gas Valve Detail
When performing a pressure test on the gas line pipng, be sure the boiler
is disconnected or isolated if the test pressure is expected to exceed 1/2
PSI (14” WC), as damage to the gas valve could occur. Such damage
could result in re, property damage, serious personal injury, or death.
DO NOT REMOVE OR ATTEMPT TO MAKE AN
ADJUSTMENT TO SCREWS 2 and 4 WITHOUT A
CALIBRATED COMBUSTION ANALYZER. DOING SO
COULD RESULT IN FIRE, PROPERTY DAMAGE, SERIOUS
PERSONAL INJURY, OR DEATH.
WARNING
WARNING
Do not re (operate) the boiler until all connections have been
completed and the heat exchanger is lled with water. Doing so will
damage the boiler and void the warranty.
NOTICE
7. Use a manometer to test the gas pressure to make sure it meets the
minimum standards and does not exceed the maximum standards
of the boiler.
8. Leak test the gas line pipe before placing the boiler in operation.
Only use approved leak detector liquid solutions to check for leaks.
9. Do not operate the boiler until all connections have been completed
and the heat exchanger is lled with water.