Kiln advice

[penumbra]

Just had to post to tell you I finally had a successful firing last night. After weeks of puzzling and testing we decided to replace the 13amp elements with 16amp ones. The kiln reached the desired temperature and faster than it has before. Still waiting for it to finish cooling to inspect the pots within but so far it would seem to be a success.

Let it cool slowly though tempted you may be.

 

[sorce]

The longer you wait to open it the better they get!

Sorce

 

[JeffS73]

Great news and an interesting idea to try!

 

[Sputnik 184]

After a couple of really successful firings I have further problems. The glaze firing seemed to be struggling to get to temperature again and while watching the controller the readout was fading in and out with sharp clicks. I tried an experimental bisque firing at lower temperatures and that also seemed to be taking longer than usual but did reach temperature and the controller screen remained constant. I now suspect the controller relay may be the cause of the problem and have ordered another but with our ongoing postal strikes who knows if it will arrive this side of Christmas. Determined to fix the problem now but it’s beginning to feel like we’re building a new kiln bit by bit.

Am I on the right track?

 

[penumbra]

Without following this thread back, did you replace the elements?

 

[Sputnik 184]

Without following this thread back, did you replace the elements?

Yes the elements were replaced and upgraded to 16amp. The cabling to the kiln was all replaced and the next two firings were really smooth. The intermittent flickering on and off of the controller display made me suspicious that was now likely to be the problem. I suspect the elements were getting to the end of their life too so I don’t think I’ve replaced in error so far. We removed the thermocouple and that seemed to both look okay and it agrees with the orton cones when firing.

 

[Pitoon]

The kiln reached the desired temperature and faster than it has before. Still waiting for it to finish cooling to inspect the pots within but so far it would seem to be a success.

Getting the kiln up to temperature faster doesn't give the ceramics inside the required heat work.

 

[Sputnik 184]

Getting the kiln up to temperature faster doesn't give the ceramics inside the required heat work.

Before I changed the elements the firing was taking 15+ hours. Now it has come down to 12-13 hours with the same firing schedule.

 

[Sputnik 184]

The relay did arrive despite the postal strikes and having fitted it we tried a glaze firing last night. The controller seemed to be running smoother and quieter and the schedule completed without faulting and in an acceptable time. Waiting for the kiln to cool now but unless there’s anything further wrong a £7 relay seems to have been the major problem. If only we’d known this earlier.

 

[penumbra]

When I was in the business we replaced a lot of relays but always in conjunction with swapping out elements.

 

[JeffS73]

The relay did arrive despite the postal strikes and having fitted it we tried a glaze firing last night. The controller seemed to be running smoother and quieter and the schedule completed without faulting and in an acceptable time. Waiting for the kiln to cool now but unless there’s anything further wrong a £7 relay seems to have been the major problem. If only we’d known this earlier.

Fantastic, I'd just be pleased it's sorted, plus you know the other bits you've replaced are good for a while now.

Please share your latest results, hope it's a like an extra Christmas present! I'm putting a bisque on today.