I-OH (01-20) PN120390R7
25
Figure 17. Heater Controls
Prime the unit (two-pipe supply):
install a pressure gauge and turn the burner on. The system will vent itself
through the return line. Flame will appear as soon as the air has been eliminated.
Check nozzle pressure:
check and adjust nozzle pressure as follows:
a. Install pressure gauge (125-psig minimum) into pressure gauge port on burner pump (see
).
b. Verify that air shutter setting (preset at factory) on burner is in accordance with
. All other controls
should be in normal position.
c. Turn OFF electrical power.
d. Set thermostat to above room temperature. Pump starts and burner ignites.
e. With burner ignited, check and adjust oil pressure if necessary to pressure of 100 pounds for unit sizes 095
and 140 or to 150 pounds for unit size 190.
Burner Electrical
Switch
NOTE: Older model
controller shown.
Primary Ignition Control
with Reset Button
Primary Ignition
Control
Table 12. Air Shutter Settings
Unit Size
Air Shutter
Air Band
CO
2
Range (%)
095
#6
#0
9–11
140
#6
#0
10–12
190
*
#7-1/2
#0
11–13
*
Unit size 190 models manufactured
before
JUN 1996 had the same settings as unit size 140.
Check draft:
prior to continued operation, check to be sure that there is sufficient draft for proper combustion. A
draft of −0.01 IN WC is required over the fire. When firing, the draft measurement in the stack should be −0.03
to −0.04 IN WC. Measure draft as follows:
a. To measure overfire draft, remove metal plug in observation door (see
Figure 18. Combustion Air Band and Air Shutter
b. Insert air pressure gauge such as Dwyer pressure gauge and observer reading on gauge.
Air Band
Observation Door
Air Shutter
