Beckett NX burner

SlamDunk

I returned to NY for the first time in five years and while there, cleaned and tuned my brother's oil furnace for the second time. Pleased to say that the furnace and stack were pretty clean. Replaced nozzle, filter, primed pump, fired it up and numbers were remarkably close to what they were five years ago. Made no adjustments.

This burner doesnt have a quiet light off. It has a "whoosh" and causes the flue damper slap. Can anything be done about this? It has done it since purchase.

Steamhead

Check the electrode adjustment- if it's too far back it can cause this.

EdTheHeaterMan

That would be delayed ignition.   Is the ignition transformer providing adequate spark?  Are the electrodes close enough to the flame to light the oil as soon as it starts coming out of the nozzle.   There are detailed specifications for those measurements.

Also, what is your fuel pump pressure? That is important.

HVACNUT

What boiler? Top or rear flue? How is the flue piped?

You didn't give combustion numbers, but it sounds like too much air. Excess air should be 25-30% with O2 between 4.5-6.5%. All while correct draft (which is what BTW?), 0 smoke, at steady state. With the Nx, I'm sure there's a pre purge. Too much air.

SlamDunk

Thanks everyone,

@Steamhead, I can readjust the ignitors when I go back up. I spent a looong time adjusting them. They kinda looked too far back yet close to original position but It does sounds like a minor, delayed ignition.

@EdTheHeaterMan, we used those dimensions, eyeballing them, as best we could, It was difficult achieving all three dimensions. We used manufacture's dims because that is what we should do but I am willing to move them up a hair.

The pump pressure wasnt checked this time because the Mitco gage was misplaced😡. But when I measured it the first time, @HVACNUT, it was set to Armstrong's recommendation but I dont recall the pressure so, no gage, no measurement and no adjustment. 145psi keeps ppping in my head but I dont trust my memory. I have the pressure requiremnt at work.

Smokepump test was 0. Analyzer's probe filter was clean.

Combustion numbers: Excess Air and O2 are slightly higher. (They used to be 5% & 30%). But not enough to force an adjustment at this time for two reasons: 1- My analyzer had issues and my confidence in it was reduced. I blame TSA😂. 2- It was hot. Ambient temp was 86f. And I didn't run furnace as long as I wanted to. Burner kept cutting off and the house was hot.

I think the electrodes might be my problem.

SlamDunk

From Armstrong Manual

From Beckett NX Manual.

I believe @Steamhead is correct. If Armstrong drawing is to scale, it looks like the electrodes are further forward than 3/32" depicted in beckett illustration. I can't make out the verbage in Fig 7. @EdTheHeaterMan the pump pressure was 145psi. Just not verified this go around.

EdTheHeaterMan

Here is the T501 gauge.

If you look close at Fig 7 you can clearly see the electrodes are further out past the 3/23 mark that is on the left bottom of the gauge. A have a feeling that the cross on the left will place the electrodes at 3/32 foreword of the nozzle and 1/4" above the centerline of the nozzle. There should be an additional Fig (maybe 8) that shows the nozzle assembly from the side (the one in fig 7 is from the top).

Not one to make waves about this because I have found that sometimes manufacturers make mistakes, but I believe the 1/4 above, 3/32 foreword, and 5/35 gap are where you want to be. You can even go as close as 1/8" gap. Any farther out than 3/32" may place the electrodes to close to the spray and you may get some carbon build up on the metal wires.

EDIT: I found the illustration of how to use the T501 gauge on the side view. It illustrates the hight and the foreword hash mark to determine the electrode position, you want to check that before (it's Figure 5), then check the Gap second (using Fig. 7.)

SlamDunk

thanks @EdTheHeaterMan

I found the T501 gauge on supply house and learned a lot that wasnt clear in the manual. Fig 7 is all there is in manual.

The electrodes are at 3/32” forward, 1/4” above ,& gapped 5/32”. we took a lot of time setting them to those dims. I appreciate the drawings and advice you provided. It could be just a junky light weight draft damper that bounces on light off.

EdTheHeaterMan

I have noticed that some Draft Controls are more sensitive to the start up of the burner than others.  The one that looks like the lid of an old metal coffee can that has the counter weight that looks like some fender washers are very accurate, but do not have that much mass to them so they react too fast to that startup "Puff" no matter how delicate it is.  The Draft Regulator from Field Controls model RC seems to be less affected by startup “Puff”.  The old Effikal dampers are also good.  But I don't know where to get them ever since Field Controls took them over. 

SlamDunk

Field control RC is what is installed. There is no heft to it at all. Thanks again.

HVACNUT

https://forum.heatinghelp.com/discussion/comment/1813467#Comment_1813467

I've got an Effikal on mine, (Riello F5) and my light off can be smooth as silk, or M80 loud, depending on what the wind is doing outside.

EdTheHeaterMan

https://forum.heatinghelp.com/discussion/comment/1813535#Comment_1813535

Then you need a wind vane with a directional control switch. That way if the wind is blowing from the wrong direction, the burner will not be allowed to light off, until the wind changes to a more silky delicate direction.

SlamDunk

I wanted to ressurect this thread to ask another question. I bought my brother a T501 electrode gage to soften the somewhat hard light off. He didnt use it yet because of the holidays-understandable.

But in the meantime, he found something online that told him to close off the firematic oil valve for this problem, so he did (2turns), and his problem went away. He asked me what would this do to the flame? I dunno. I dont know why that would work. It probably does nothing to the flame because he isnt starving the pump. And the pump pressure is fixed. What are the ramifications of this tactic?