Hi , can you see the piezo making a spark?.if not then you may need a new piezo or lead . if you can see sparking it could be the pilot is blocked and needs cleaning.
Also if you can light the pilot with a taper through the viewing window , this would prove the pilot is OK
Hi! Your answer was very helpful. Until I can get a new piezo I hope its ok to just light thro observation pane and then replace the latter. Once the pilot is alight the heater works well. Thanks for your advice..........Mike.