Unit installation

30
MAIN BURNER
ASSEMBLY
PILOT BURNER
ASSEMBLY
FIGURE 19
• The pilot flame should envelop sensing device with 5/8"
(1.6cm) flame, fig. 21. Remove pilot adjustment cover screw,
fig. 22. Turn inner adjustment screw clockwise to decrease, or
counterclockwise to increase pilot flame. Be sure to replace
cover screw on gas valve after adjustment to prevent possible
gas leakage.
2. Clogged pilot burner orifice.
• Clean or replace orifice. A clogged orifice will restrict gas
flow.
3. Incorrect orifice.
• Replace. See Table Vll, for correct orifice for type of gas
used. Orifice size is stamped on the wrench flats.
Pilot sensing device must sense a flame before sparking will stop.
Loose wires or a draft may cause intermittent or abnormal
sparking. To eliminate this condition, first correct loose wiring
condition, and then, if necessary, increase pilot flame.
PILOT BURNER ASSEMBLY
FIGURE 20
MAIN BURNER
The main burner, fig. 21, should display the following
characteristics:
• Cause rapid ignition and carry over of flame across entire
burner.
• Give reasonably quiet operation during ignition, burning and
extinction.
• Cause no excessive lifting of flame from burner ports.
TYPICAL PILOT AND MAIN BURNER FLAMES
FIGURE 21
If the preceding burner characteristics are not evident, check for
accumulation of lint or other foreign material that restricts or blocks
the air openings to the burner or heater.
NOTE: Cleaning of main burners.
1. Remove main burners from unit.
2. Check that burner venturi and ports are free of foreign matter.
3. Clean burners with bristle brush and/or vacuum cleaner —
DO NOT distort burner ports or pilot location.
4. Reinstall burners in unit. Make sure front and rear of burners
are installed correctly in burner support brackets.
Also check for good flow of combustion and ventilating air to the
unit. Maintain a clear area around the heater at all times.
GAS VALVES
Figure 22 shows the type of combination manual gas control
valve and regulator used on these heaters.
FIGURE 22