IBC EX Series, Installation & Operating Manual

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3. Set the heat-out value in manual mode to the minimum MBH for the boiler. To do this:
a. Go to Main Menu > Diagnostics > Test Operation .
b. Click inside the Fan Test: Heat Output box, and using the number pad, enter the
minimum MBH.
c. Select OK . The fan runs to the minimum MBH you have set. Select the Fan Test: Heat
Output box to change the heat out value.
4. Low fire adjustment - adjust the low fire according to see Table 11 using a Phillips head
screwdriver. Turn clockwise to raise the CO
2
% (to richen). Turn counter-clockwise to lower
CO
2
%. Start with ⅛ of a turn until you see the analyzer measure a change then only make
1/16 adjustments. If changing direction on this adjustment you may notice a significant
backlash.
5. Check the results and confirm the correct settings when you return the boiler to high fire, and
then to low fire.
Note
Clock the gas meter to confirm full maximum rating plate input.
6. To exit the Test Operation screen, select Back .
7. Remove call for heat.
8. Turn off the gas supply at the external gas shut-off valve.
9. Remove the analyzer probe, and install the test port plug.
10. Disconnect the manometer.
11. Tighten the inlet pressure port screw with a flat head screwdriver.
12. Turn on the gas supply shut off valve and test for gas leaks.
Fuel High fire Low fire
CO max
PPM
Range % Target % Range % Target %
Natural Gas
9.0 - 10.0 9.5 8.2 - 9.2 8.7
<150
Propane
10.3 - 11.3 10.8 9.3 -10.3 9.8
< 250
Table 11 Combustion test target ranges - CO
2
/ Maximum CO
75
6.3.4 Adjusting the gas valve (EX 400, EX 500)