Been adjusting and cleaning my Weil Mclain/Becket burner for years. Replaced filters and nozzle. Got the adjustment of the electrodes down fine. Specifications say to set the Z distance from the nozzle to the heat shield face at 1 3/8 inch. If I do, I'm back in there in 6 months to clean the nozzle and heat shield. If I set it to 1 1/16th inch, it runs well for over a year and isn't that dirty when cleaning time comes around. What should it really be set at?