Measure and adjust manifold gas pressure (36J54 valve)

What is going on

Manifold pressure is measured with burners operating. Only small variations should be made with the valve pressure regulator. Do not derate the furnace by setting manifold pressure below the rating plate value.

Likely causes

• Manifold pressure outside the table range
• Regulator out of adjustment

Check in this order

1. Shut off gas at the manual shutoff, then shut off all electrical power.
2. On the White-Rodgers 36J54, back the outlet pressure test screw out one turn counterclockwise (no more than one turn).
3. Attach a hose and manometer to the outlet pressure tap.
4. Turn on gas and power, then run the high fire or low fire test.
5. Adjust the high fire or low fire regulator so manifold pressure matches the table.
6. Turn off gas, remove the manometer and reinstall the test screw and plug.
7. Turn on gas, check for leaks and verify operation.

More furnace guides

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