Kiln malfunctioning : Three Kiln “ERR” s in a 17 hour long bisque fire!!

[Jeanetta]

I’m a total newbie at firing (these details will attest). .. but am trying to figure out my next steps after my first firing being a failure. I’d love to just hire a kiln tech as I’m not very adept with these things. But I live in a remote place & so far haven’t been able to find someone specializing in kilns. Any tips to narrow down troubleshooting would be greatly appreciated! And/or tips on finding techs or working with general electricians!

I was gifted a Gare kiln (model #PF2329) with a “perfect fire” programmable display. I had a general electrician hook it up, do some quick tests and from what he could tell it seemed fine.

I ran my first bisque fire the other day (& night) watching it like a hawk and recording the temp every 15-30 min. I confirmed the perfect fire program was set for a ramp rate of 300 F/hr, and to cone 06. One of its features is called “soft fire” and the manual advises using this feature, which I did. I had three witness cones in (05,06,07) but in the end couldn’t see them as I didn’t have welders goggles (lesson/woops #1)

anyhow when I realized I was staring into the sun I decided to put my trust in the computer’s temp (woops #2 perhaps).

the ramp rate of 300 degrees/hr progressed fine over the first couple hours.... but then slowed down to 200/hr then 150, 100, then eventually 50 degrees per hour around 1600... and 14 hours later it was progressing at a creeping painful increases of 30 degrees/hour. The soft fire directions said it might slow down/control as things got super hot so I assumed this is what it was doing.

HOWEVER around the 12 hour mark (@ 17000 ish degrees) the kiln started beeping and read “ERR”. The temp dropped a bit but i restarted it. It continued a few hours then The beeping error & stop happened again at 1770, and again after a couple hours at 1780.

At 1780 & three errors later I figured it was close enough, I was knackered 17 hours in at 5am and shut it all down at that point.

I emptied it today and discovered all three cones in a smooth glassy blob! So it obviously got way too hot in there! The pieces look and feel overfired. I’m resigned to chalk this up to learning and wont bother trying to glaze (embracing the fact that I now have many many flower pot mugs!).  Woops #3 don’t be so overly excited & neglect to do an empty test fire with a new used kiln!

What I’m most concerned about is figuring out how to troubleshoot and get a functioning kiln. Any opinions and thoughts majorly appreciated- I’m flying blind here as a highly inexperienced kiln operator.

my sincere thanks

 

 

[Bill Kielb]

Sounds like not enough power to reach temperature at a reasonable rate. 30 degrees per hour at the end won’t get it done so likely elements are worn more than 10% from new which is generally when they get replaced. You can estimate when a cone falls simply by following the cone chart. The rule is the last segment of the firing should be the last 200 degrees and the rate should match the chart.

So in the chart below it would be common for an 04 firing, pick an ending rate (108 degrees per hour, center column, note # 2) pick an ending temperature from the column (1945, cone 04) and subtract 200 degrees, 1945-200=1745. Start your final segment at 1745 degrees at 108 degrees per hour and you should approximate cone 04.

The last 200 degrees of the firing (note #1) is where the significant heatwork is done. At some point as kilns wear they cannot make this rate and all other things considered the elements have worn too much to finish the firing at an acceptable rate. While your kiln does not have to go exactly 108 degrees per hour, it needs to be reasonably close. The 27 degree per hour  column will work, but not for long and from reading above you did not make 1798 or cone 06 in the 27 degree per hour column.  Very likely if all elements glow, it’s time for new.

[neilestrick]

Maybe fried an element or relay as it got hotter, then couldn't keep up. Unplug it, open up the control box, and see if there are any fired wires. Then start it up at 100% and see if all the elements glow after a few minutes.

[Jeanetta]

Thank you kindly for your thoughtful replies. This is very helpful stuff on my steep learning curve!! !
I am firing it right now with the lid open to check the elements. (I also got ahold of Evenheat and a technician told me to do this test too). Within the first 6 min The top 2 and bottom 2 are glowing. I’m waiting on the rest to glow now.
Perhaps of note: the glowing isn’t the same depth/intensity orange all the way around....the glow is patchy in spots . Could this indicate worn elements?

visually the coils seem ok everywhere (& I don’t think broken from what I can tell...though I don’t know exactly what I’m looking for) but the bottom 2 rows stand out as the coils look a little wonky (will try to attach a pic)

[Jeanetta]

[Jeanetta]

Update at 40 min in (set for ramp rate of 3,900 , no hold time) this is what it looks like. None of the inner 8 elements are glowing.

[Bill Kielb]

1 hour ago, Jeanetta said:

Update at 40 min in (set for ramp rate of 3,900 , no hold time) this is what it looks like. None of the inner 8 elements are glowing.

After all that,  since they don’t all glow next likely culprit is a bad relay or two and of course the outside possibility that a wire connection has burned and corroded or come loose. The elements don’t look the greatest so I think I would plan on replacing them all if you intend to keep the kiln and regardless you will need to learn how to troubleshoot relays. They should make a clicking noise when they turn on so that is one way to tell if they are not engaging which is pretty indicative that they are bad but not a 100% check.

So my best thought would be it appears pretty worn but a relatively nice kiln so I would be inclined to replace the elements and relays and have a nice mostly new kiln that ought to last quite some time. My thought is relays last a bit longer than elements but my guess is that kiln has a decent amount of firings on the elements and relays so if it’s a keeper, it might be best to plan for an overhaul.

Still troubleshooting the center elements is likely wise which means a technician or a bit of learning how to measure things with an ohm meter. And at one point you did say this kiln was heating at 300 degrees per hour or so which is unlikely with only two elements glowing so this likely died in the firing. . Lots of youtube videos out there and as long as the POWER IS OFF testing is pretty safe.

[Jeanetta]

Thank you so much Bill, I appreciate this advice and your taking the time to give it!!

As this is all pretty out of my wheelhouse & aptitude ...I’m learning so much, fast!

What you say makes sense so I suppose my next challenge is to figure out replacing things as you say (i’d like to make use of the kiln). Leading me to one last question I guess: is replacing elements & relays the sort of thing a general electrician should be able to handle? (Has anyone had experience with this?) Or should I put some real effort into getting a proper kiln technician to travel my way? (I live quite remotely).

with gratitude

[neilestrick]

1 hour ago, Jeanetta said:

Leading me to one last question I guess: is replacing elements & relays the sort of thing a general electrician should be able to handle?

No, not really. Relays yes, elements, no. But relays are super simple to replace. There are lots of good video tutorials on replacing elements, so if you're physically able to do the work it would be good to learn to do it yourself.

As for your kiln, it looks like it's probably wired up with the 4 middle elements running on one relay, and the top and bottom each on their own relay, and the middle relay is dead or there's a fried connection. You'll need to open it up and see how it's set up, but that would be my best guess. If one relay is dead, it's a good idea to replace them all if it dies due to age, because they all wear at the same rate. Your elements don't look great, so it may be a good time to replace them too. 

[Jeanetta]

Thanks so much!

[Jeanetta]

Wanted to update on this in case anyone else is in a similar boat and finds the info useful:

with your helpful feedback I set my sights on upgrading the elements and relays. I called Evenheat and the technician kindly also explained some stuff.

we tried the paper test on the elements and as they didn’t completely burn he similarly assessed the relays needed replacing. When I asked about elements he advised that he’s been noticing a fair amount of the “perfect fire” controllers starting to crap out (I guess they’re older), so there may be a risk that by overhauling this kiln (elements are expensive)  I may only find the controller goes (crazy expensive) and I’d be out all that’s money.

SO wanted to share he advised an option of just replacing relays (affordable) and even with worn elements it might still be ok as a bisquing kiln. Which is an interesting thought.

since I need a kiln asap and am feeling risk averse I’m going to buy a brand new kiln, then maybe learn about relay replacement and try to use this one as a  bisquing kiln.

the learning journey continues!

[Bill Kielb]

12 minutes ago, Jeanetta said:

since I need a kiln asap and am feeling risk averse I’m going to buy a brand new kiln, then maybe learn about relay replacement and try to use this one as a  bisquing kiln.

the learning journey continues!

Congratulations on getting a new kiln. One thought comes to mind especially if you need one quickly. It might take time to build and ship so it still might be worth ordering two or three relays for the old kiln. If it works, you can bisque as planned and if necessary try a glaze.

[Jeanetta]

Ooh That’s a super helpful tip- thank you!!!