Thermocouple - WarmGlass.com

Thermocouple

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Aglassygirl303
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Thermocouple

Postby Aglassygirl303 » Sat Nov 08, 2014 5:16 am

I have a Olympic 186GFELTC kiln with a Bartlett 1000 controller. I just replaced the lid and elements, had Olympic put the elements in the lid for me. Hooked it up and it heated to 880 degrees, slowly I might add. Then it posted an e-1. The Elements heated up fin, so not the new elements. So we replaced the relay switch. Just fired it up and again E-1 at 880. The thermocouple has never been replaced. Do they wear out? And how do I know. I am not getting a FAIL message. And a e-1 is indicative of many thing including a "failing TC". Any advice. I'm so frustrated I am about to throw the kiln in the street! It holiday time and I am getting very behind

I run this kiln 5-6 days a week. Thanks

Stephen Richard
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Re: Thermocouple

Postby Stephen Richard » Sat Nov 08, 2014 6:01 am

I suggest you contact Olympic for guidance
Steve Richard
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Aglassygirl303
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Re: Thermocouple

Postby Aglassygirl303 » Sat Nov 08, 2014 6:34 am

Thank you Stephen. I have been in constant contact with Olympic. They are the ones that have been guiding me, if you want to call it that. I'm so frustrated with the indirect guidance I have been getting. All that I get are in conclusive answers. Maybe it is this and maybe it is something else. This is a nightmare

Tony Smith
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Re: Thermocouple

Postby Tony Smith » Sat Nov 08, 2014 9:26 am

Thermocouples don't wear out, but they can be damaged. If there's no evidence of physical damage, like a crack or severe bend, and the temperature reads properly at room temperature with an upward trend as the kiln heats up, it's unlikely to be your problem.

Did you verify that all of your elements were glowing red as it heated up?

Tony
The tightrope between being strange and being creative is too narrow to walk without occasionally landing on both sides..." Scott Berkun

Aglassygirl303
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Re: Thermocouple

Postby Aglassygirl303 » Sat Nov 08, 2014 3:44 pm

Thanks Tony, of course as I said in my post, all elements do light up beautifully and even, they are brand new. The relay swith was replaced yesterday. If you look up Thermocouples, they do in fact wear out. I spoke to two Kiln Repair Technicians this morning and they believe that I have a TC that is going bad, hence why I am not gettin a FAIL message We are replacing the TC now. So hard to get to on the Bartlett Controller. Anyway, thank you.

suds
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Re: Thermocouple

Postby suds » Sat Nov 08, 2014 9:22 pm

Yes, type K thermocouples can "wear out".
After a lot of heating and cooling cycles the chromel/alumel junction can crack (sometimes not at the junction itself but at the edge of the heat affected zone where it's welded) and lead to flakiness and sometimes they go open above a certain temperature like yours appears to be doing.
A good thermocouple should last a very long time in a glass kiln because the temperatures are relatively low. Doing high fire ceramics where temps regularly go above 2100F is much harder on them.

I had the misfortune to work in a tile factory for a couple of years and replaced countless type K thermocouples.
Steve

Aglassygirl303
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Re: Thermocouple

Postby Aglassygirl303 » Sun Nov 09, 2014 12:06 am

Can it be a problem with the Bartlett RTC 1000 Controller/Kiln Sitter? Like the circuit board not working anymore? Kiln is now at 800 and it does not seem to be ramping up at 350 dph. Slowing down at the same point. What would cause the ramp speed to go slow.
Re cap-
Brand new lid with elements installed be Olympic Kilns (Original issue, elements channel was pretty destroyed in original lid after a few element replacements, kiln wires fried at point on connection to elements)
Brand new Relay switch
Brand new Thermocouple

Please, anyone

Kevin Midgley
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Re: Thermocouple

Postby Kevin Midgley » Sun Nov 09, 2014 2:26 am

Low voltage feeding the kiln?
Weather getting colder and you have an appliance that is drawing more electricity now running?
Connections in wall plug may be failing.
Sick breaker in the fuse panel?
Cord to kiln replaced with a smaller gauge ie skinnier wire when lid redone?
An amp clamp could reveal power being used.
Check the wiring in the building.
Suggest an electrician do it for you to be safe.
Loose wiring connections that only fail when heated?
Wrong elements installed in kiln lid? A definite possibility.
You may have 220 volt element wiring instead of the 110 the kiln is rated for.
Call the electrician in is the final answer.
yes it will cost but so will lost production time.

Aglassygirl303
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Re: Thermocouple

Postby Aglassygirl303 » Sun Nov 09, 2014 3:01 am

Thank you Kevin, it just failed. E-1 at 887

Olympic installed the elements into the lid, could they have put in the wrong ones??? How would I know that they are the wrong elements. Olympic set up the lid so that all I had to do was connect the new lid. They did almost sent the wrong relay switch but corrected and sent the correct one.
The wires to the old lid and element were fried on one side. Not sure what had happened. We have new wires and maybe should try to replace them.
Kiln has its own dedicated plug/circuit breaker.
Could it be a bad transformer?

Aglassygirl303
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Re: Thermocouple

Postby Aglassygirl303 » Sun Nov 09, 2014 3:23 am

Update. This kiln is fitted with wall elements. This model lets you choose which to use, lid or wall. I never use the wall, but I just now fired them up and VIOLA they are working. I am at 900 and rising. So perhaps my voltage is ok after all and the issue with the lid wiring. I wonder still how will I know if they installed the wrong elements. This is the largest model possible for the 120 line. The next size up would have a larger lid so those elements would not likely even fit, so my common sense whispers. Okay, fire away

Bert Weiss
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Re: Thermocouple

Postby Bert Weiss » Sun Nov 09, 2014 2:07 pm

Thermocouples degrade such that they read a lower temperature than when working properly. Most thermocouples I have seen in manufactured kilns are exposed welded ends. These will degrade quickest. I recommend an inconel sheathed 1/8" diameter thermocouple. I just replaced mine after 24 years of use. I use a company called Krumor in OH, that makes them to order. You specify diameter, length, and what kind and length of wire ends.

Otherwise look for poor electrical connections anywhere on the control or element circuits.
Bert

Bert Weiss Art Glass*
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Aglassygirl303
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Re: Thermocouple

Postby Aglassygirl303 » Mon Nov 10, 2014 2:38 am

Thank you Bert, I have it all running now. There was a fried wire that connects to one of the elements. My husband is going to be replaceing those wires in th next few days. I need to catch up on a few orders first. Right now I am having some good firing with the body elements. I did not know that you could use "other market" components. I did replace the TC, the old one was bent. It is sheathed. The only damage was the bend, no corrosion or cracks.

I am so thankful for all this input.

Bert Weiss
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Re: Thermocouple

Postby Bert Weiss » Mon Nov 10, 2014 12:29 pm

Aglassygirl303 wrote:Thank you Bert, I have it all running now. There was a fried wire that connects to one of the elements. My husband is going to be replaceing those wires in th next few days. I need to catch up on a few orders first. Right now I am having some good firing with the body elements. I did not know that you could use "other market" components. I did replace the TC, the old one was bent. It is sheathed. The only damage was the bend, no corrosion or cracks.

I am so thankful for all this input.
The business end of a thermocouple is simply the tip where the 2 wires are welded together. So, a bend would only be a problem if it messed up the weld or the wires.
Bert



Bert Weiss Art Glass*

http://www.customartglass.com

Furniture Lighting Sculpture Tableware

Architectural Commissions

Aglassygirl303
Posts: 47
Joined: Sun Nov 08, 2009 10:08 pm

Re: Thermocouple

Postby Aglassygirl303 » Mon Nov 10, 2014 1:41 pm

Well I now have a new TC, Relay switches, elements and lid, all is well with my world. Happy glass melting to all 8)

Aglassygirl303
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Re: Thermocouple

Postby Aglassygirl303 » Thu Nov 20, 2014 12:53 am

POST MORTEM So, all of the little parts replace, down to the wires, literally and my kiln lid still would not heat past 880. It ramped perfectly to 600 but by 700 it slowed down to a few degrees per hour. I eventually got some help from Bartlett, wonderful technician that worked with me troubleshooting. We ran all kinds of tests but he eventually referred me back to Olympic. So I called and here is the end result. They installed the lid with a 220 element!!!!! My kiln is a 110! So I spent the better part of a month attempting to make it work. Everyone advised that it was a power issue, but all of that had checked out. I am quite relieved. Olympic customer service, tech dept, and the owner graciously fell on their sword, apologized, and are immediately shipping me a new lid with the correct elements installed. Thanks for all the trouble shooting assistance. It was a power issue all along, my poor kiln just did not have the power to heat those 220 elements. All will be will soon :)

Bert Weiss
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Re: Thermocouple

Postby Bert Weiss » Thu Nov 20, 2014 11:51 am

Aglassygirl303 wrote:POST MORTEM So, all of the little parts replace, down to the wires, literally and my kiln lid still would not heat past 880. It ramped perfectly to 600 but by 700 it slowed down to a few degrees per hour. I eventually got some help from Bartlett, wonderful technician that worked with me troubleshooting. We ran all kinds of tests but he eventually referred me back to Olympic. So I called and here is the end result. They installed the lid with a 220 element!!!!! My kiln is a 110! So I spent the better part of a month attempting to make it work. Everyone advised that it was a power issue, but all of that had checked out. I am quite relieved. Olympic customer service, tech dept, and the owner graciously fell on their sword, apologized, and are immediately shipping me a new lid with the correct elements installed. Thanks for all the trouble shooting assistance. It was a power issue all along, my poor kiln just did not have the power to heat those 220 elements. All will be will soon :)
With half the power, getting up to temperature is impossible. Glad you solved the problem. Of course, what happened makes perfect sense...
Bert



Bert Weiss Art Glass*

http://www.customartglass.com

Furniture Lighting Sculpture Tableware

Architectural Commissions

suds
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Location: Sonoma County, CA

Re: Thermocouple

Postby suds » Thu Nov 20, 2014 2:18 pm

Bert Weiss wrote:With half the power, getting up to temperature is impossible. Glad you solved the problem. Of course, what happened makes perfect sense...


With 1/2 the voltage, the element only draws 1/4 of the wattage it normally would. No wonder it was struggling!
Steve

Aglassygirl303
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Re: Thermocouple

Postby Aglassygirl303 » Thu Nov 20, 2014 11:41 pm

It was the most frustrating experience.we have been at this for a month and could not get it solved. Thankful we got to the bottom of it. :roll:


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