Saunier Duval ISOFAST F 28 E, Инструкция по установке и эксплуатации

Страница: 29 / 32

29
FAULT FINDING
Before trying to operate the boiler make sure that :
• All gas supply cocks are open and that the gas sup-
ply has been purged of air.
• The heating system pressure is at least 1 bar.
• There is a permanent mains supply to the boiler.
• The fuse on the PCB is intact.
WARNING. Always isolate the boiler from the electri-
cal supply before carrying out any electrical replacement
work.
Always check for gas soundness after any service work.
Should there be any doubt about the voltage supply to
any of the components, it is possible to carry out a sim-
ple electrical test to ensure all is operational in that area.
To carry out the electrical test, gain access to the main
Printed Circuit Board (PCB), as described previously,
and measure the voltages according to table 1.
The ISOFAST has an on-board fault diagnostic system. Should a fault occur on the boiler, the warning LED at the top
of the user display will illuminate and the LCD display will indicate the precise area where the fault has occured.
Table 1
Voltage Measured value Measuring point
230 Volt 230 V AC Between terminals H8.1 and H8.2
24 Volt maximum 33V DC Between terminals B2.4 and B2.7
minimum 20V DC
15 Volt 15V + 0.5V Between terminals B2.4 and B2.2
Display 5V + 0.5V Between terminals B2.4 and B4.2
09 FF
Sec 052
A fault code is displayed on the left hand side of the LCD display, whilst at the same time, the letters FF appear with
a telephone symbol.