Lennox FCM 85 Installation, Operating And Maintenance page 82

HEATING : MODULATING GAS BURNER 180 & 240 kW
- Check the 230V supply voltage of electronic boards: the
phase on terminal 01 and the neutral conductor on terminal
02
- Check the wiring of the signal 0-10V between terminal 64
(polarity 01 of the 24V) and terminal 66 (+ coming from the
actuator)
- Check the connection of the modulating solenoid valve
between the electronic board's terminals 61 & 62
- Select the operating mode n°3 "output
0-330mA":
The minimum pressure setting must first be
adjusted to ensure that burner will safety
light up, then maximum pressure setting
can be adjusted.
Any adjustment of the minimum pressure
influences the maximum pressure setting.
Any adjustment must be done with flat
spanners.
Adjustment of the W4115D1024 board's potentiometer:
- Connect the Multimeter with Micro-
Amps scale in serial with the
MODUREG.
until the desired
is obtained: here, to reach 8.0mbar, we must apply 105mA,
according to the curve below.
FLEXYII_WSHP-IOM-0909-E
•
Switch n°1 ON
•
Switch n°2 OFF
- To prevent
hysteresis, place
the potentiometer
called "current"
on position Min.
- Increase the
current by turning
this
potentiometer,
maximum current
Adjusting minimum pressure setting:
- Disconnect electrical connection to MODUREG
(=modulating solenoid valve)
- Regulate the value of the minimum flow at 2.2mbar (for
natural gas and at 3.0 mbar for Groningen gas) by turning
the adjusting nut "Maximum pressure".
Adjusting maximum pressure
setting:
- By Pushing the shaft gently
downwards to the maximum
adjustment screw, you'll see an approximate value of the
maximum pressure
- Reconnect the electrical
connection to MODUREG
- Regulate the value of the
maximum flow at 8.0mbar (for natural gas and at 10.4mbar
for Groningen gas) by turning the potentiometer called
"current", until the desired maximum pressure.
When maximum and minimum pressures are set wire the
valve in the circuit.
- Now, check the good reaction of the assembly,
MODUREG + electronic board, by applying 2 V to its input
(=climatic 50 output); it must reach the minimum pressure
(2.2mbar for natural gas)
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