Kiln Vent Still Smelling

[Jeanetta]

I have an Orton vent master on my Skutt 1027 kiln.

I don’t think it’s ever really been working properly since I first installed it (have done maybe 10 firings since install) as each time I can still smell some off-burning during firing.

The install: We carefully followed the instructions that came with the vent. We drilled two holes in the top of the lid and three holes in the bottom being very mindful of course that they fits within the collector cup diameter. The  cup is snug up against the base and all the ducting appears to be tight as far as I can tell.

I don’t think air pressure should be an issue as the kiln lives in a really big draughty old mill with giant doors open, so to my understanding this shouldn’t create pressure problems.

The vent leaves one part of the building directly at the wall and then goes straight up and out a little chimney on the roof that we formed and added a little arch cap to allow exit but prevent rain .

Am Including photos here of the set up.(When I was ordering the kiln vent I ran these plans by the supplier and he said this should all work fine).

So I’m totally confused! I don’t know why this isn’t working.

I just recently did my first firing since a big winter pause and there was so much moisture stream was coming out of the sides of the lid- I wound up turning off the fan vent and just propped the lid and removed a bung. I could hear some pieces breaking as well, eek! (very nervous to open when it finishes) eventually the steam all came out and I’ve closed the lid at 1000 F.

This extreme steaming thing is new, I’m hoping it was maybe just from excessive moisture accumulated over the damp and icy cold winter season & hopefully won’t reoccur (the bisque ware shouldn’t be wet…) or the steam was maybe exacerbated by it being pretty windy today….But either way I would’ve expected the vent to be extracting what it needed to if there was moisture….?

Regardless the vent setup has never functioned completely without some smell no matter the climate , winds or season.

When I have been using the vent I keep all the bungs in and the lid is a good tight fit.

1 ) any thoughts tips or ideas???

2 ) In the meantime (as I need to get firing), should I fire the old way before I had the vent? - propping the lid until 1000° then closing it and leaving the top bung out? Now that I have these holes existing in the top and bottom will this old method be problematic?

3 ) to fix the vent issue maybe I need another hole drilled in the bottom? Or my loads are too full? The instruction manual says heating rates shouldn’t be more than 300 Fahrenheit per hour but my cone fire program automatically does greater ranges than that at times…. I wonder if this could be a problem?

4)Also-  this may be a ridiculous question but I can’t get my head around the holes in the Collector cup that attached to under the base of the kiln. How does that work with suction? Aren’t those holes letting the gases escape? It seems like a big area for holes to exist when I’m trying to remove everything from the kiln and keep all the other connections tight….

Thank you so much for your time!

 

 

 

[Bill Kielb]

So many things, so little space. The collector cup must have holes, mainly room air and a small amount (Tiny) of kiln air are intended to be exhausted. Never cover the holes in the cup! The cup needs to mount tightly against the floor of the kiln, sort of an air tight connection. Did this cup come with a spring to hold it up against the bottom of the kiln? These vents work pretty well when properly configured. Not all fumes but a good majority.

Nothing will remove steam quickly enough so dry everything out first before firing and enter a reasonable preheat time to remove the water slowly. Steam means water but also means you made it to boiling too quickly.

Herr is a nice video. At 8:38 have a look at how her vent stays in contact with the bottom of her kiln. https://youtu.be/6laQqL-neAU
 

 

[Jeanetta]

Haha yes that was a lot!

thank you for your explanation of the cup, and your thoughts

The cup does have a spring, and it fits quite snugly.

Helpful to read your words about steam too

[Mark C.]

Your vent stack is long-hopefully the cap (for rain is not slowing down the exhaust) that air needs to move freely.

As bill said steam means to fast. (wares are wet) slow it down-preheat slowly

That flex pipe really slows down air (the non smooth inside is bad for air movement)It looks like you could hard pipe that as well easy ands that will increase air flow alot.