Temperature Regulator Not Working

[AndreaB]

Hi, I'm hoping someone can point me in the right direction regarding the inaccuracy of my temperature guage readings. I usually fire to 1200 deg C but my guage  setting is totally inaccurate. It started when I replaced the thermocouple recently. According to the cones it was out by 30 deg. This has slowly increased to the point where on my last glaze fire the cones (6 and7) were completly melted, fusing to the cone holder.

I called a local chap who fixes kilns and he suggested I get a digital controller. Will this sort the problem out or should I be looking for another solution?

 

Thanks.

 

Andrea

[Marcia Selsor]

you could program by temperature and just set it for 30 degrees higher.and use a guide cone.

Marcia

[neilestrick]

So this is a manual kiln? Does it have a kiln sitter like we use here in the US? Post a picture if you can.

[AndreaB]

This is my "controller". The kiln was made in SA and quite a while ago. The company who made them no longer exists.  In other words the controller is me. I manually set the temperature guage in 1hr intervals. Ramping 150 deg at a time.  Using the dial on the right to increase the level of heat 1 being very low and 6 being full blast.

 

 

Marcia,

I don't understand your reply.  The temperature guage reading is incorrect showing a lower temperature than what the kiln actually is firing to.  Meaning the guage reads 1100 and the temp inside the kiln is around 1180.

 

By the way the picture was taken with the kiln switched off at the plug and circuit board

 

Andrea

[Chilly]

 

 Meaning the guage reads 1100 and the temp inside the kiln is around 1180.

 

 

What are you using to measure the temperature?

 

Are you sure it is calibrated correctly?  

 

I have a number of thermometers in the house and greenhouse, and they all read differently at room temperature.  At higher temps the differences are likely to be greater.  I also have a digital thermometer that came from a test department, and was calibrated yearly.  This is the only one I really trust, and even now (7 years since I acquired it) it is likely to be out of calibration.

[Babs]

Place your cones so they're visible and turn off when lead cone is touching toes. I wouldn't fire on temp alone

[Mark C.]

(Place your cones so they're visible and turn off when lead cone is touching toes. I wouldn't fire on temp alone)

yes use cones not this device-its only a guide-cones are more accurate .

[neilestrick]

There's no way an old analog pyrometer like that is going to be accurate enough. Put some cones in the kiln and watch them bend. Use appropriate safety glasses so you don't hurt your eyes. A #5 welding lens is cheap and effective.