Nordyne M1G Control Module Status Indicators - M1M Series, Control Module Status Indicator - M1B

Control Module Status Indicators - M1M Series

Control Status

The Red LED labeled “STATUS” is provided to indicate system faults.

Steady ON:	Control OK
Steady OFF:	No power
Rapid flash:	False flame or internal control fault
One flash:	Limit switch is open
Two flashes:	Pressure switch is open
Three flashes:	Pressure switch is stuck closed
Four flashes:	Lockout due to failed ignition
Five flashes:	L1 neutral reversed or L1 voltage
	not present on L1

Flame Status

A Yellow LED labeled “Flame” is provided to indicate flame status. When flame is sensed, the flame LED is lit. If flame sense is weak, yellow LED will flash.

Control Module Status Indicator - M1B

a. One flash-the control is in lock-out because the inducer centrifu gal switch is or was stuck closed.

b. Two flashes-the control is in lockout because the signal was not received by the control that the inducer centrifugal switch had closed within the time.

c. Three flashes-the control is in lockout because a failed ignition attempt, a gas valve error, or a false flame sensed during the warm up period. If false flame has been sensed, the control will return to normal operation, and repeat ignition sequence when the false flame is not present.

d. Four flashes-the control is in lockout due to a failure within the control board.

Control Module Status Indicator - M1S* Series

The indicator light on the oil primary control provides lockout, recycle, and cad cell indications as follows:

1.Flashing 1/2 second on, 1/2 second off - system is locked out or in restricted mode.

2.Flashing 2 seconds on, 2 seconds off - control is in recycle mode.

3.Indicator light is on - cad cell is sensing flame.

4.Indicator light is off - cad cell is not sensing flame.

may be defective. Replace the gas valve if necessary.

e. Be sure the pilot shield is in place.

f.Check for gas leaks in the pilot line or the pilot assembly.

g.Check the flue assembly to make sure all connections are tight.

h.See the FURNACE START-UP procedure for lighting details.

Main Flame Is Not Burning Properly a. Check the manifold gas pressure.

b. Check for the correct main burner orifice. - See the nameplate SPECIFICATION.

c. Check the flue for any blockages or loose connections.

d.Check the combustion air passages for block- age.

High Gas Bills

a. Be sure the proper orifices are being used.

b.Be sure the return air system is clear and free of blockage.

c.Be sure the furnace filter is clean.

d.Be sure the home is insulated, that windows and doors fit tightly, and that there are no leaks in the heating duct system.

e.Check the room thermostat to be sure the setting is not higher than necessary. Low

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