Check inlet gas pressure at the boiler

What is going on

Use a manometer on the line pressure test point to confirm the inlet gas pressure is within the minimum and maximum for the gas type. Loosen the bolts before checking the inlet pressure. Do not change screws 2 and 4 (OFFSET and throttle) unless you have a calibrated combustion analyzer.

Check in this order

1. Turn off the gas supply and confirm the boiler is isolated if the test pressure will exceed 1/2 psi (14 in WC).
2. Remove the yellow cap from the line pressure test point.
3. Unscrew the P in screw.
4. Connect the manometer to the test point.
5. Read the inlet gas pressure and compare it to the gas pressure table.
6. Disconnect the manometer.
7. Tighten the P in screw.
8. Leak-check the connection with an approved leak detector solution.
9. Replace the yellow cap.

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