Kiln shutting off

[Kim Manley]

Looking for hints about what might be wrong before I call the kiln people over from the other side of the city (and have to pay a call out). Temps are in celcius (I am in Australia)

Kiln fire successfully through:
70 degrees per hour to 210 degrees
200 degrees per hour to 500 degrees - hold for 5
Is then supposed to fire at 300 degrees per hour to fusing temp

1 & 2 are being completed successfully, fails on 3 and return an error message (ERR1) that means the kiln has not increased temperature by more than 8 degrees an hour (and in fact the kiln temp is falling).

As the kiln is firing successfully to 500 degrees I presume the element is not an issue. Any quick fixes or do I need to "suck it up" and pay the specialist to come over?
(p.s. its a Stafford controller)
(p.p.s I lived in Staffordshire until my father moved us half way around the world as children)

Any help would be appreciated.

[Brad Walker]

Does the kiln have two or more sets of elements? It's possible that one set is working and one isn't.

[DonMcClennen]

I would start by erasing existing problem program then re-entering same in a different user slot (eg: user4 instead of user2). As we all know these digital devices sometimes have a mind of their own.

[Morganica]

Besides elements, could be a relay issue. My kiln does that when it's time to replace a relay--kiln isn't getting as hot as expected by the firing program, so it eventually shuts down.

Also (and this is a VERY longshot), I once had a kiln failing with that error on some firings while others were perfectly fine. I'd just replaced the relays so I called the manufacturer, and we did a lot of testing--the kiln was perfectly fine. Finally, their engineer asked how much venting I was doing, and if the kiln was exposed to any kind of moving air...bingo.

Turned out the firings that were failing were all casting projects with mold drying cycles, where I vent the kiln about 2 inches to let water vapor escape. It was a hot month, so I left the studio (garage) door wide open to catch the breeze. The kiln was right in front of the door, and apparently enough air was getting into the kiln to cool down the thermocouple and confuse the controller. I shut the studio door--no more kiln failure.

But like I said, that's a longshot.

[Kim Manley]

I think there is only one element (small kiln) about 12 inches cubed. Will reheat to see if this is so. Safety switches on lids / doors in Australia to have to get up to highish temp and whip the door open to see.

Hopefully it isn't the controller as it is less than a year old.

Its 5 am here and after having a house full of uni (college) students last night for my daughter's 21st birthday I am ruminating over the kiln problem instead of sleeping.

[Stephen Richard]

Sounds like programming problem. Like Don says, reprogramme.

[Kim Manley]

Took the side off the control. I do have two elements and it appears there may be a problem with one of the switches. I will be calling the kiln techs on Monday.

[Kim Manley]

The photos should be rotated 1/4 turn clockwise! The bottom of the kiln is on the right of the photo.

[Arnold Howard]

1 & 2 are being completed successfully, fails on 3 and return an error message (ERR1) that means the kiln has not increased temperature by more than 8 degrees an hour (and in fact the kiln temp is falling).

Your safety switch may be out of adjustment. (The safety switch turns off power to the elements when the lid or door is open.) If the safety switch is only slightly out of adjustment, the elements will sometimes still heat at lower temperatures. At higher temperatures, though, expansion of parts can cause the safety switch to turn off the elements before the kiln has reached the programmed temperature.

Sincerely,

Arnold Howard
Paragon Industries, L.P., Mesquite, Texas USA
ahoward@paragonweb.com / www.paragonweb.com

[Kim Manley]

Thanks Arnold - Tetlow did suggest adjusting the safety switch, and luckily for me the technician was out at one of the local schools, called in and changed the relay over as it was burnt out. Just waiting for the bill (can't actually believe there are still businesses that don't want payment on the day). It is now happily firing (as is my little Paragon test kiln - love it).