11
9) Burner Adjustments. Allow the burner to operate steadily for 5 to15 minutes. Check
burner settings shown on the Installer/Service Man Label and make the following adjust-
ments.
a) Punch or drill a 1/4” hole in the flue pipe between the boiler and the barometric draft
regulator. All test readings should be taken from this point.
b) Take a draft reading from the flue pipe sampling hole. Adjust the draft in the stack,
using the barometric draft regulator, to the value shown on the Installer/Serviceman
Label. In tall chimneys a second draft regulator may be required in the flue pipe to
regulate draft under high draft conditions.
c) Remove the draft port plug over the fire and take a draft reading from the draft port.
Compare the readings with those on the INSTALLER/SERVICEMAN label. Refer to
the trouble shooting procedure if the draft over the fire reading is not correct.
Reinstall the draft port plug after all readings have been taken.
d) Follow the burner manufacturer’s instructions to adjust the air supply until a trace of
smoke is recorded. At the trace of smoke level, measure the CO
2
. This is the refer-
ence point for all further adjustments.
e) Increase the air supply to reduce the CO
2
about 1-1/2% to 2% from the reference
point. A zero smoke reading should result. If this adjustment can not be obtained,
refer to the Trouble Shooting section of this manual.
f.) When combustion is set, follow the burner manufacturer’s instructions to lock or
tighten adjustment mechanisms as required.
10) Check operation of the cad cell relay by removing one cad cell wire from external termi-
nal during the flame cycle. The relay should cut the burner off in approximately 15 sec.
11) Direct Vent Applications. The burner control for direct vent applications is provided with a
post-purge feature to keep the burner fan operating after the flame is off. The post purge
cycle time is 120 seconds. See the burner manufacturer’s operating instructions for more
information on the post purge settings.
E. Servicing the Boiler/Burner Unit:
1) Burner Components: If replacement of burner parts is necessary, always use parts
recommended by the manufacturer. Specify part number and description when ordering.
2) Electrode settings are important for reliable ignition of the fuel. Check to be sure the
settings are in accordance with the instructions provided in the burner manual.
3) Nozzles: The nozzle specifications listed in the manual are the result of years of exhaus-
tive engineering testing. Use extreme care in handling nozzles to avoid scratches or dirt
that could cause leaks or affect the fuel spray pattern.
CAUTION:
Any nozzle replacement should be of the exact type as listed in the
specifications.
