BASO Pilot Burners User Manual
Page 4

4 Pilot Burners/Thermocouples Technical Bulletin
2. Reduce the flame on the pilot through the use of the “B” valve to the
point where the open circuit millivoltage reading is not more than
4 millivolts.
3. Cycle the main burner On and Off at least three times. The main
burner must ignite each time within four seconds.
If you cannot secure ignition of the main burner when the millivoltage
reading is 4 millivolts, the pilot has been located improperly with respect
to the main burner. Relocate the pilot; repeat Steps 2 and 3.
If you do not have the Y99AB Test Kit, perform the turn down test using
the following steps:
1. Reduce the flame on the pilot, through the use of the “B” valve to a
point where the pilot flame does not impinge on the thermocouple
(see Figure 3).
This flame must ignite main
burner as long as . . .
. . . This flame keeps
BASO On.
Inlet Fitting
Marking
burnflam
Figure 3: Turn Down Test without Instruments
2. Cycle the main burner On and Off at least three times. The main
burner must ignite each time within four seconds.
3. Then wait at least three minutes for the BASO to drop out. (Main
burner flame will go out.)
4. If the BASO does not drop out, reduce the pilot flame further and
repeat Steps 2 and 3.
Turn Down Test
without
Instruments