CT SERIES BOILERS - Columbia Heating

3. Start the burner. After the prepurge is complete, the pilot will light and indicatebetween 1-1/2 and 4 microamps. The main gas valve should try to open andindicate power between terminals MV-MV.4. Reduce the size of the pilot flame to the turndown position by slowly closing themanual valve on the pilot gas line. At the turndown condition, the pilot will besmall enough so it just barely causes the main gas valve to open (about 1 to 1-1/2 microamps.).a. slowly turn down the pilot until the main gas valve will not open and the burnershuts down on flame failure. NOTE: The burner motor will continue to run.b. Allow the burner to complete prepurge. If the control locked out, reset thecontrol by depressing the reset switch for sixty seconds and restart the burner.c. As the control attempts to restart the pilot, turn the pilot back up slowly untilthe gas valve tries to open.d. Again turn the pilot down slightly but not enough so the flame drops out. Ifthe relay drops out simply repeat step c above. If the control locks out allowthe safety switch to cool, reset the switch, and repeat step c.5. Check that the pilot is lit and the gas valve is trying to open.6. Open the manual main burner gas cock. Main flame should light within one second.If the burner does not light within one second, close the shutoff cock andshut off power to the relay. Proceed to step 8.7. If the burner lights, repeat step 6 a number of times to verify the light off.Proceed to step 10.8. If the light off is unsatisfactory, readjust the flame detector to require a largerpilot flame to cause the main gas valve to open.a. Adjusting the flame rod detector so that a larger minimum pilot flame isrequired by moving the flame rod farther from the grounding rods.9. repeat the entire turndown test until the flame is established promptly in stepnumber 6.10. Turn the pilot up to full flame at the completion of the test.FM-148 COLUMBIA BOILER COMPANY, REV 6-06- 37 -