cad cell damaged

Charlie from wmass

New one for me. The cad cell was burnt crispy on one side, the side towards the electrode. Carlin 301 burner on a Weil 480. What could have caused the spark to jump? The gap is correct and the burner works fine with simply replacing the cad cell. 2 hour drive to the burner is no fun without getting paid for it. Burner was installed in November brand new with the boiler. Thanks for the help guys.

rick in Alaska

Usually when I see a melted cad cell it is because of a back draft through the burner. Generally caused by something like an exhaust fan running in the room . The fact that it was only burnt on one side is a little weird for that scenario though. Did it look as if it was an electrical arc caused, or from excessive heat?
Other than back drafting, I can not think of any other reason for a burnt cad cell.
Rick

Marz

The 480 is a positive draft boiler. I would check the damper adjustment in the back of the boiler and maybe try to get a +.02 overfire.

Charlie from wmass

One side only.

Charlie from wmass

page 32 of manual calls for .01 positive pressure at damper.

billtwocase

Charlie, how did the buss bars look? Arcing maybe? Does this have a pre and post purge set? Any sign of negative pressure in the boiler room? That is strange

Charlie from wmass

huge basement old house bus bars are straight. It has been a weird job all winter long. Bad tiger loop, burner control died in February, and oil tanks leaked in March. The tanks were made in 1996.

Charlie from wmass

pre and post purge. It is a brand new burner and boiler. Huge chimney. It looks like there was an arc as it is burnt on the side towards the buss bar and it not burnt at the end facing the flame. I will see if it is in my scrap bucket and grab a photo.

billtwocase

I would like to see a pic of it. I just love jobs like those that Murphy's Law has control over it. Just finished one like that. Possible grounding issue with the electronic ignitor? Hope all is well with you after this winter. You had a tough one out there

EBEBRATT-Ed

That sucks. Draft issues is my first thought but being burnt on one side doesn't make sense. Cracked electrode making the spark jump through the cad cell?

We use to check for cracked electrodes by putting a pc of glass between the electrodes as an insulator and seeing if the spark jumps somewhere where it shouldn't.

Last Monday was a bad Karma day for me. Went to disconnect a ac unit outside on a slab. My battery sawzall charger died so I couldn't charge a battery, I pulled out my Milwaukee cord sawzall that was rebuilt two months ago and that died, then I pulled out my porta band and on the first cut the blade got pinched and broke!!!

Then the crane operator stopped by to look at the job as the pick was the following morning at 6 am. We talked a few minits when he got back in his truck it wouldn't start!!

Harvey Ramer

Some days it's not worth getting out of bed.

EBEBRATT-Ed

Harvey Ramer Posts: 971Member ✭✭✭

11:09AM



Some days it's not worth getting out of bed.

Ain't it the truth!

burnerman_2

Seems like every year there is that one job.... nothing goes right...

Charlie from wmass

This is the one that I have for sure.