W6A/W15A UL flame not start

If you have symptoms like no flame, no ignition, no alarm on your W6/15 UL machine

Basic troubleshooting:

• - check the Max temperature switch(Clixon), usually located on the exhaust pipe in the back of the machine. You can reset it by pressing the small button in the middle of the sensor

• - check that internal cyclone doors are closed. Both doors have sensors. If the door is open ( or the sensor is broken), the power cuted to the BCU(burner control unit).

• - check that the connector is well connected to the BCU(burner control unit)

• - check the gas supply: gas valve is open, enough inlet pressure in the gas supply

Note: if the pressure - PA is not stable or cannot reach the PA set point, the burner will not start 

Additional troubleshooting steps:

 - open the control panel and check if the relays 301K1, 301K2 and 505K1, all this relas should be active otherwise, the burner will not start up

- sometimes contacts are stuck inside the relay, so you can remove each relay and make a light finger kick, then put it back 

Advanced electrical chain diagnostic:

To perfrom this doagnostic we would recommend to arrange a professional electrician 

Allocate the electrical schema/drawings on the USB flash drive that comes with the roaster's documentation.