NTI INSTALLATION MANUALS

Part 8 - Gas Connections

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.

To check inlet gas pressure: 1. Remove yellow cap from line pressure test point. See Figure 74. 2. Unscrew “P in” screw. 3. Connect the manometer to the test point. 4. Check the inlet gas pressure. 5. Disconnect the manometer from the test point.

6. Tighten the “P in” screw (1 N/m). 7. Check for and repair any gas leaks. 8. Replace the yellow cap.

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 73.

IN

Figure 73 - Excess Flow Valve (EFV)

WARNING

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.

Figure 74 - Remove Yellow Cap

WARNING

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.

D. Checking Gas Pressure at the Boiler for Proper Operation

NOTE: Refer to Figure 74 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 23.

4

2

Natural Gas

1

Minimum Pressure

3.5” WC

Maximum Pressure

10.5”WC

LP Gas

Minimum Pressure

8” WC

Maximum Pressure

13”WC

Table 23 - Gas Pressure Requirements

1. Line pressure Test point 2. OFFSET Adjustment Screw 4. Throttle Adjustment Screw

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

Gas Inlet

Figure 75 - Gas Valve Detail

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