Benchmark MAIN User Manual

52
17.0 Fault Finding
© Baxi Heating UK Ltd 2007
Replace PCB
G
Check and correct if necessary
1. Ignition electrode and lead
2. Electrode connection
3. Spark gap and position
230V at PCB - A1 connector
across terminals
3 & 4. Check wiring
YES
NO
Replace gas valve,
electrical plug &
igniter assembly
YES
H
YES
Check the burner setting pressure of the
gas valve
(see Section 9.2 of Commissioning)
1.
Voltage at modulating coil of gas valve is:
Max. burner press.approx 9V DC (13V DC LPG)
Min. burner press.approx 1V DC
Current at modulating coil of gas valve is:
(Use an instrument with average function for this
measure)
30 ÷ 230 mA DC (45 ÷ 310 mA DC LPG)
Replace gas valve
NO
Replace PCB
2.
Check and correct if necessary
1. Flame sensing electrode and lead connections
2. Electrode position
Flame current should be 1 μA approx.
Replace PCB
Replace PCB
NO
YES
Replace flame sensing electrode
NO
YES
Ensure that mains input terminal L
is Live (230V) and N is Neutral
(0V)
I
Check terminal 1 of On/Off/Reset selector is in
connection with PCB - A4 connector terminal 2
Check electrical continuity across terminals 1 & a of
On/Off/Reset selector when turned to position
R
Replace On/Off/Reset selector
NO
Replace PCB
YES
K
Replace overheat
thermostat
YES
YES
Overheat thermostat operated or
faulty, i.e. continuity across
thermostat terminals
Allow to cool. Continuity
across thermostat terminals
more than 1.5 ohm
J
If checks in section I are completed successfully, blockage of the
condensate drain or trap may have occurred
L
If checks in section J are completed successfully, the flue overheat
thermostat may have operated. Press the reset button on the flue
overheat thermostat. If the boiler does not relight or repeatedly
cuts out. Check the operation of the flue system or replace the
flue overheat thermostat
M

Benchmark MAIN Specifications

General

Brand	Benchmark
Model	MAIN
Category	Boiler
Language	English