Fault Diagnosis - Blue Sea EVOLUTION G47 Service Manual

5.2 Fault Diagnosis

5.2.1 Pilot Drops Out
Pilot flame too small
If the pilot can be lit but the flame is too small to impinge on
the thermocouple, then check the gas pressure. If ok, then
remove the pilot injector from the pilot burner and check for
blockages and / or correct size.
Pilot Burner
Figure 5.2.1a
Thermocouple faulty
Check the thermocouple connection is firm and the safety
cut-out lead connection to the interrupter block on the
thermocouple is secure. (Loose connections will cause
resistance in the millivolt circuit and result in pilot outage.
If all connections are satis, light the pilot and whilst holding the
control knob in, measure the voltage from the pilot side of the
connecter block to earth (e.g. the body of the control valve).
This should read approximately 30mV.
If this reading is less than 20mV and there is good impingement
of the pilot flame onto the thermocouple, the thermocouple is
faulty - replace the thermocouple.
Control Valve
Pilot side of Interrupter Block
Figure 5.2.1b
Safety cut-out tripped
The safety cut-out is set at 115°C. If there is water in the tank
and the safety cut-out has tripped (open circuit) then the safety
cut-out is faulty.
Blue Seal Evolution Series - G47 Gas Pasta Cooker
Amendment 6
Safety cut-out faulty
To check if the safety cut-out is faulty hold in the gas control
button and light the pilot (leaving the control button depressed
to keep the pilot alight). With a multimeter measure the voltage
from the gas control side of the thermocouple interrupter block
to earth. If the voltage is under 5mV (and the thermocouple is
generating at least 20mV) then the safety cut-out is faulty -
replace the safety cutout.
If all of the above checks out ok then check gas control or
thermocouple.
Control Valve
5.2.2 Piezo Ignitor Not Sparking
Short in high tension lead
If repeated sparking of the piezo shows only intermittent
sparking at the electrode, then the lead should be traced to find
the area of short. This can be visually seen as the spark arks.
If the lead is shorting the best solution is to replace it, as the
electrical insulation of the lead may have deteriorated.
If the spark arc can be seen at the electrode insulator at the
pilot burner instead of at the electrode tip, then the insulator
probably has a fracture and should be replaced.
Piezo ignitor faulty
If no spark at all can be generated, remove piezo ignitor and
hold close to cabinet body. Depress the piezo ignitor and if a
spark cannot be generated to the cabinet body the piezo ignitor
is faulty and should be replaced.
Note: If piezo ignition fails, the pilot can be manually lit
using a standard taper torch, lighter or matches,
until the piezo circuit is repaired.
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Fault Finding
Gas Control side of Interrupter Block
Figure 5.2.1c
Figure 5.2.2
© Copyright Moffat Ltd, March 2016
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