Checking Manifold Pressure

Attention! If one of the above procedures results in pressures in excess of 1/2 psig (14" w.c.) (3.5 kPa) on the appliance gas valve, it will result in a hazardous condition.

Both Propane and Natural gas valves have a built-in pressure regulator in the gas valve. Natural gas models will have a manifold pressure of approximately 4.0" w.c. (.996kPa) at the valve outlet with the inlet pressure to the valve from a minimum of 5.0" w.c. (1.24kPa) for the purpose of input adjustment to a maximum of 10.5" w.c. (2.615kPa). Propane gas models will have a manifold pressure approximately 10.0" w.c. (2.49kPa) at the valve outlet with the inlet pressure to the valve from a minimum of 11.0" w.c. (2.739kPa) for the purpose of input adjustment to a maximum of 13.0" w.c. (3.237kPa).

A1/8" (3mm) N.P.T. plugged tapping, accessible for test gauge connection, is located on the outlet side of the gas control.

The built-in regulator comes on at approximately 1/4th pressure and full on in 10 seconds.

Figure 9

High Altitudes

For altitudes/elevations above 2,000 feet (610m), input ratings should be reduced at the rate of 4 percent for each 1,000 feet (305m) above sea level. For Canadian high altitude applications, this appliance is suitable for installation at elevations between 0 feet (0m) and 4,500 feet (1,372m) without change.

Piezo Pilot Ignitor Instructions

Depressing the red button completely causes a spark to occur at the pilot. This is a substitute for a match which requires opening the pilot hole cover.

To light the pilot, it is important that the electrode be 1/8" (3mm) from the thermocouple. The spark must occur at the point the burner ﬂame hits the thermocouple. The end of the electrode will be red hot with the pilot on.

On a new installation with air in the gas line, it is suggested that a match be used. The match will light the pilot faster than the piezo under this condition.

Proper Pilot Flame

The correct pilot ﬂame (Figure 10) will be blue, extending past the thermocouple. The ﬂame will surround the thermocouple just below the tip.

Natural gas pilots require adjusting when the inlet gas pressure is above 5" w.c. (1.245kPa). Remove the pilot cover screw on the control valve (Figure 9), and turn the adjustment screw clockwise to reduce ﬂame. Replace pilot cover screw to eliminate gas leakage.

LP gas (propane) will not require adjustment.

After use, cleaning may be required for the proper ﬂame.

Proper Main Burner Flame

The correct ﬂame will be a short, blue inner ﬂame with a much larger, light blue, outer ﬂame. The burner does not have a primary air adjustment. The ﬂame will be correct if the factory-set pressure and oriﬁce opening are used. After the furnace has been operating, the burner ports may be blocked by foreign matter carried in by combustion air. Therefore, cleaning of the burner may be needed for proper ﬂame.

To clean burner port disconnect the gas supply to the valve, and remove the screws fastening the burner door. After removing the burner door

Page 8

from the burner box, remove each main burner. Pilot mounting bracket will need to be unscrewed and moved out of the way to remove all burners. Burners can be blown out using compressed air or by blowing through them. Be sure there is no lint or foreign debris blocking the burner ports. Reassemble using the same screws earlier removed and locate pilot in the same position as before and noted above.

THERMOCOUPLE

		BURNER
SPARK�	PILOT
ELECTRODE	PILOT
ELECTRODE
	STANDING PILOT
THERMOCOUPLE		PILOT SHIELD
		PILOT SHIELD
SPARK�
ELECTRODE

PILOT LOCATION END VIEW

STANDING PILOT SHOWN

3/8" TO 1/2"�

PILOT FLAME

GROUND�

ELECTRODE

BURNER

PILOT

HOT SURFACE�	FLAME�
IGNITOR	ROD

IP-MODEL PILOT

Figure 10

Figure 11

Cleaning Combustion (Exchanger) Assembly

A QUALIFIED SERVICE PERSON should remove the combustion (exchanger) assembly and ﬂue bafﬂes. Apply air pressure to the inside of the combustion (exchanger) assembly and ﬂue bafﬂes in order to clear all passageways.

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