Pilot Flame Characteristics; Main Burner Flame Characteristics - Empire Heating Systems RH-50-7 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 yel-
low 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.
31910-4-0115

PILOT FLAME CHARACTERISTICS

On Propane gas, if a whistling noise (resonation) oc-
curs
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 12.
Figure 6
Figure 5
Page 11