Pilot Flame Characteristics; Main Burner Flame Characteristics - Empire Heating Systems RH-50-6 Installation Instructions And Owner's Manual

The correct flame will be almost horizontal, blue and will extend
past the thermocouple 1/4" (6mm). The flame will surround the
thermocouple just below the tip.
On Propane (LP-gas) slight yellow might occur where the pilot
flame and the burner flame meet.
Natural gas pilots require adjusting when the inlet pressure is
above 5" w.c. (1.25kPa). Remove pilot adjustment cover. Turn
adjustment screw clockwise to reduce flame.
Propane (LP-gas) will not require adjusting.

MAIN BURNER FLAME CHARACTERISTICS

There will be a short blue inner flame with a larger, lighter blue secondary flame. The burner flame may have yellow tips when hot.
Dust in the combustion air will produce and orange or red flame. Do not mistake the orange or red flame for an improper yellow flame.
The flame will be proper if the factory-set pressure and orifice are used. After use, cleaning may be required for the proper flame.
On Propane gas, if a whistling noise (resonation) occurs
a. Screw the air adjustment bolt into the burner throat to eliminate the whistling noise (resonation).
b. Size main burner orifice with a drill bit. For RH-50(C) use #47 drill bit. For RH-65(C) use 2.3mm drill bit.
Primary Air Adjustment see page 11.
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PILOT FLAME CHARACTERISTICS

Figure 6
Figure 5
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