White Rodgers 50E47-843 Installation Instructions Manual Download Page 4

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INSTALLATION

INSTALL PROGRAM KEY

The control replaces all listed models with the following
features:

•  120 volt hot surface ignitor
•  remote rod flame sense or direct flame sense through ignitor
•  one or three ignition tries
•  Seven or four second trial for ignition intervals
•  Pre-purge of 30 seconds or less
•  60 second inter-purge time
•  17 or 45 second ignitor warm-up times

Six program keys are provided for different applications.
Timings and Retries for each program key are shown in the

Specifications section of this installation manual. Choose the

proper program key for the application by using the Module
Cross Reference (37-7209). Install the selected program key in

the slot on the left side of the module (see figure 4 on page 3).
If the module you are replacing is not listed in the Cross
Reference, contact the manufacturer of the appliance for a
recommended replacement or retrofit.

After inserting the proper program key, dispose of the
remaining keys to ensure the correct key remains in the

module.
Reversal of gas valve leads or open connection to MV1 and

MV2 may cause control to lockout. See troubleshooting guide

for remedy.

OPERATION

TROUBLESHOOTING

TYPICAL FURNACE INSTALLATION

In a typical application the 50E47-843 is designed to energize

the ignitor and gas valve and monitor the flame sensor. It

is a 100% shut off design that locks out the gas valve if the

burner does not light within the trial for ignition period. The

ignition sequence begins with a call for heat from the room

thermostat. The thermostat applies power to the control.

After pre-purge interval, the ignitor warms up for the selected
time. The control energizes the gas valve for the selected

trial for ignition period. If the burner lights within the allowed
period the gas valve will remain open until the call for heat
is satisfied. During the trial for ignition period the ignitor is
turned off. If the burner does not light, the control will either

go into lockout or make two more ignition retries depending
on the options selected. The control can be reset from lockout

by cycling the thermostat to remove power for a minimum of

3 seconds. It includes a system analysis/troubleshooting LED
that indicates normal operation, lockout, weak flame signal or

internal control fault.

For proper control operation, the control must be electrically
connected to the gas valve and all the ignitor wiring connec-

tors plugged in. Gas valves with an electric "ON/OFF" switch

must have the switch set to "ON".
The light on the control provides a self-diagnosis indication.
If the red light on the module is on continuously, the fault is

likely to be internal to the module. To make sure, interrupt

the line or 24 volt thermostat power for a few seconds and
then restore. If the internal fault is indicated again, and flame

sensor is not shorted to ground, replace the control. A flash

ing light indicates the problem is most likely in the external

components or wiring (see chart below). Proceed as follows:

Three visual checks

1.  The ignitor will warm up and glow red
2.  The main burner flame will ignite
3.  The main burner flame will continue to burn after the

ignitor is turned off

Troubleshooting the system consists of checking for these

three visual indications. The chart on the next page defines
the proper action if any of these indications do not occur.

LED

Condition