Columbia EMG-31 120 Instructions Manual page 9

18) Attach a 1/8" NPT nipple and stop cock to the outlet side of the gas valve.
Regulator
Adjustment
Screw
19) Attach a manometer to the nipple / stop cock assembly and take a reading of the gas pressure.
20) Make sure the manifold pressure is set at 3.5" W.C. Adjustments can be made to the
manifold pressure by turning the set screw located on the gas valve. Gas pressure is
increased by turning the set screw clockwise and decreased by turning the screw
counterclockwise.
21) Allow the boiler to fire for a period of 10 – 15 minutes in order to reach the desired operating
temperature.
22) Take a flue measurement at the sampling port. Draft should be slightly negative for chimney
vent applications (-0.01" to -0.04"). Adjustments to the draft can be made by installing a
listed draft inducer or draft regulator.
23) Take a CO measurement using a combustion analyzer. Adjust the air shutter so that the CO
2
reading measures 9.0%. Increase the air shutter opening to decrease the CO
decrease the air shutter opening to increase the value.
24) Use the combustion analyzer to verify that the CO level is below 100 ppm and that the flue
temperature is above 375
25) Cover the drilled out sample port either by applying a silicon sealant or high temperature
tape. It is important to cover the sample port to prevent flue gases from infiltrating through
the opening.
Annual Maintenance Requirements
1) Inspect gas line for leaks.
2) Inspect exhaust venting for leaks.
3) Clean blower wheel.
4) Inspect electrode tips for unnecessary wear.
Take an ohmmeter reading of the flame sensor.
5)
6) Clean air intake.
7) Inspect coil gasket (retighten bolts if necessary).
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F.
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value and
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