Adjustments And Checkout - Honeywell C7024E User Manual

UV SENSOR TUBE TEST
For initial burner lightoff, consult the burner manu-
facturer instructions or the instructions for the flame
safeguard control.
If the system does not start during the initial burner
lightoff, check the UV sensor tube in the flame detector.
If a reddish glow appears when there is no flame present,
replace the UV sensing tube. When performing this test,
make sure there are no extraneous sources of ultraviolet
radiation in the test area. See Radiation Sources section.
ADJUST DETECTOR SIGHTING
With the flame detector installed and the burner run-
ning, adjust the detector sighting position for optimum
flame signal.
Most existing Honeywell Flame Safeguard Controls
incorporate a flame current jack on the control flame
amplifier or on the control itself. Measure the flame
signal with an ohm/volt meter (see Fig. 11) such as the
Honeywell W136A Volt meter.
Fig. 11—Measuring voltage flame signal with
7800 SERIES controls.
NEGATIVE (-)
METER LEAD
The R7824C Amplifier used with the RM7824 Flame
Safeguard Control has a dc voltage flame signal output. For
the R7824C Amplifier, an ohm/volt meter with a minimum
sensitivity of 20,000 ohms per volt with a zero to five or
ten Vdc scale is recommended. Measure the flame signal
as illustrated in Fig. 11. Be careful to make the proper
connections of the positive (red) meter lead to positive (+)

Adjustments and Checkout

POSITIVE (+)
METER LEAD
20K OHM/
VOLT METER
M7554
control jack and negative (black) meter lead to negative
(-) or common (COM) jack with the R7824C Amplifier. If
the RM7824 Control has the Keyboard Display Module
(KDM), a zero to five Vdc voltage will be displayed on
the module.
NOTES:
1. For a C7024E or F, the shutter operation causes
fluctuations in the current reading. Read the aver-
age stable current, disregarding the peaks.
2. The flame signal must be steady (or stable as
described in note 1).
Move the detector and sight pipe around to sight the
flame from various positions and angles. Try to get a
maximum steady (or stable) reading on the meter. The
signal must be above the minimum acceptable current
listed in Table 1.
Measure the flame signal for the pilot alone, the main
burner flame alone, and both together unless monitoring
only the pilot flame when using an intermittent pilot, or
only the main burner flame when using direct spark
ignition. With the detector in its final position, all re-
quired flame signals must be steady (or stable) and as
specified in Table 1. If you cannot obtain the proper
signal, refer to the Troubleshooting section.
PILOT TURNDOWN TEST
If the detector is used to prove a pilot flame before the
main fuel valve(s) can be opened, perform a Pilot Turn-
down Test before welding the sight pipe into position.
Follow the procedures in the Flame Safeguard Control
instructions and in the burner manufacturer instructions.
ULTRAVIOLET RESPONSE TEST
IGNITION SPARK RESPONSE TEST
Test to make certain the ignition spark is not actuat-
ing the flame relay in the flame safeguard control:
1. Close the pilot and main burner manual shutoff valves.
2. Start the burner and run through the ignition
period. Ignition spark should occur, but flame relay
must not pull in. The flame signal should not be
greater than 0.25 Vdc for RM7824 control.
3. If the flame relay does pull in, reposition the detec-
tor farther from the spark, or relocate/resight the detec-
tor to eliminate/reduce the detector response to reflected
UV radiation. It may be necessary to construct a barrier
to block the ignition spark from the detector view. Con-
tinue adjustments until the flame signal due to ignition
spark is less than the flame signal value indicated in step
2 above.
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C7024E,F
ADJUSTMENTS AND CHECKOUT
65-0156—1