Nu-Way MOL 3400-410, Installation & Maintenance Manual

FAULT FINDING 

If the Burner Fails to Start 

Make sure that all the thermostats and switches in the control circuit are in the ‘made’ position and that 
the oil pre-heater ‘excess limit’ thermostat has not tripped.  Reset if required.  Check that the low oil 
temperature thermostat is set correctly for the appropriate fuel. 
 
Check that the electricity supply to the burner is ‘live’ and that the control and main circuit fuses are intact.  
If a fuse is found to be ‘blown’ then the cause should be investigated and rectified before proceeding 
further. 
On steam boilers, check that the ‘water level interlocks’ are in the ‘made’ position. 

If the burner is found at lockout (red lockout lamp illuminated) 

Reset the burner and observe the starting sequence.  (make reference to the 

Sequence Diagram and Timing 

Charts 

for the Flame Failure controls on page 27 for further information

.

Check the fan and oil pump motor overloads and reset if necessary. 
Check the operation of the air pressure switch.  Failure of the switch to operate prevents the oil pump from 
starting. 
 
 

Flame Occurs Followed by Immediate Lockout

Check the PE cell and the air regulator for correct operation.  Check that the oil pressures are correct.  If 
necessary, check and clean the pre-heater hot oil filter, ensure that there is sufficient oil in the storage tank, 
bleed the oil pump in case it is partially air-locked.  Check to ensure that all stop/fire valves in the supply 
line are fully open.  Check residual fuel oil temperature – check the ring main for correct operation in 
respect of temperature and pressure. 
 
 

The Burner Starts With The Correct Oil Pressure But No Flame Appears

Check the ignition system, HT lead connections, electrode gap and the condition of the electrode 
insulators.  Check that the nozzle cut-off is functioning and that the air damper cable is not broken or 
disconnected (the air regulator will be fully open).  

It is important to note that continued re-setting of 

the burner should be avoided as this can lead to a dangerous situation.

Modulating System

If malfunction of the modulating controller RWF 40 is suspected, check that only compatible components 
such as the range insert and pressure/temperature detector have been used.  If problems persist then 
replacement of the unit should be considered. 
 
 

Burner Commissioning Sheet

This manual contains a record of the essential information and will have been completed by the 
commissioning engineer with individual details of the burner.  These details should be verified periodically 
and adjusted if variations are noted.  Commissioning details must also be record in the 

appliance logbook

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MOL 3400-4100  Issue 2   10/08 

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