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C7005A,B GAS PILOT AND FLAME ROD ASSEMBLIES
Adjust Flame Rod Position
The pilot flame must make good contact with the flame rod
and furnish reliable ignition for the main burner. Check to be
sure that the flame rod is located at the junction of the main
burner flame and the pilot flame. Ensure that the main valve
opens or unlocks only when the pilot flame is strong enough
to ignite the main burner.
Secondary air velocity over the pilot nozzle must not cause
unstable flame contact with the flame rod, because this
produces chattering of the flame detector relay.
Measure the Flame Signal
With the pilot and main burner(s) operating, adjust the position
of the flame rod for optimum flame signal (current or voltage).
Most existing Honeywell flame safeguard controls incorporate
a flame signal jack located on the control amplifier or on the
control itself. These controls require a Honeywell W136A Test
Meter (see Fig. 7) or its equivalent for measuring the flame
signal in microamperes. The flame signal (current) is
measured by the following procedure:
Use a Honeywell W136A Test Meter. (If a W136A is not
available, a microammeter with a 0 to 25 microamp dc
range can be used.)
W136A TEST
SELECTOR
METER
SWITCH
RED (+)
METER
LEAD
BLACK (–) METER LEAD
Fig. 7. Measuring microamp flame signal.
Set the selector switch on the test meter to 25 uA for all
standard amplifiers and flame safeguard controls, or to
SPL for an R7247B AMPLI-CHECK™ self-check
rectification amplifier. (If the test meter is not a W136A,
shunt the 0 to 25 microamp dc range with a 50
microfarad capacitor.)
Use a 196146 Meter Connector Plug (ordered
separately). Connect the red spade tip to the red (+)
meter lead and the black spade tip to the black (–)
meter lead.
60-2033—3
196146 METER
CONNECTOR
PLUG
PLUG
FLAME SIGNAL
METER JACK
PLUG-IN FLAME
SIGNAL AMPLIFIER
RED CONNECTOR
BLACK CONNECTOR
M6532
Insert the plug into the flame signal meter jack and
allow a few seconds for the meter reading to stabilize.
When using a RA890H,J self-checking flame safeguard
control, press the test button on the control to stabilize
the current reading while making the measurement.
The green flame indicating lamp should be on
continuously while reading the flame signal.
Read the average stable current. For an R7247B
self-check rectification amplifier (AMPLI-CHECK™),
disregard the peaks due to self-checking operation. The
red flame-indicating lamp on an R7247B should blink
about 2-1/2 to 4 times a second (from bright to dim). If
the lamp is on or off continuously while reading the
flame signal, replace the amplifier.
NEGATIVE (-)
METER LEAD
Fig. 8. Measuring flame signal voltage
of 7800 SERIES control.
The meter reading must be as specified in Table 1 after
all tests are completed and all adjustments are made.
With the Honeywell 7800 Series controls, the flame signal is
measured in Vdc. The voltage flame signal measurement
requires a volt-ohmmeter with a minimum sensitivity of one
megohm/volt and a 0 to 5 or10 Vdc scale. To make the flame
signal measurement on 7800 SERIES controls, use the
following procedure:
Set the meter to the appropriate scale.
Insert the positive (red) meter probe into the positive (+)
jack of the 7800 SERIES control amplifier and the
negative (black) probe into the negative (-Com) jack of
the amplifier (see Fig. 8).
Allow a few seconds for the meter reading to stabilize.
When using an AMPLI-CHECK™ amplifier, read the
average stable voltage and disregard the peaks due to
the self-check operation.
The flame signal voltage must be at least the minimum
acceptable voltage as indicated in Table 1.
If the 7800 SERIES control has the optional Keyboard
Display Module, the flame signal will be displayed on
the module.
6
POSITIVE (+)
METER LEAD
ONE
MEGOHM/VOLT
METER
M7382
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