metal and mud Posted February 8, 2012 Report Share Posted February 8, 2012 Hi Experienced Potters-- I was incredibly lucky to run across an old 10-sided Paragon kiln about 18 months ago. (It had been stored in an "old lady's" garage for years.) It's presence in my life got me into pottery and I love it so much I can't remember life without it. An electrician worked on the breakers in my garage and adjusted its electrical connections just a little bit and--voila--it had worked beautifully for about a year. The kiln sitter went off as expected and the firings were just right. Lately, though, things have gone bad. One cone 6 firing took too long, based on my records of how long it took, but then I learned that it didn't fire enough and the glazes didn't vitrify. I got a pyrometer after that firing and have gathered valuable information. I originally placed the pyrometer in the lowest peep hole plug, but noticed that the temperature wasn't rising very fast. In fact, I noticed the lowest segment of the kiln was rather cool and the upper ones were warm and eventually hot. That was a bisque firing to 04. The kiln sitter cone tripped the sitter at a decent temp and all works were OK. For the subsequent glaze firing I placed the pyrometer in the middle plug, thinking that perhaps the bottom element wasn't working well. I placed cone 6 cones on all three levels in the kiln. The top cone melted to a proper cone 6 firing, but the middle and lower cones did not. In fact, the bottom cone barely bent. I know that means that the heat level isn't equal at all levels. It appears that, based on the lights on the front of the kiln, electricity is making it throughout the elements in an appropriate fashion. Buying a new kiln is out of the question. Would you experienced potters try replacing the elements? Is that hard to do? I'm so unhappy this has happened. I apologize for the length of this post, but I sure would like some advice from you non-newbies out there. Link to comment Share on other sites More sharing options...
Arnold Howard Posted February 8, 2012 Report Share Posted February 8, 2012 I got a pyrometer after that firing and have gathered valuable information. I originally placed the pyrometer in the lowest peep hole plug, but noticed that the temperature wasn't rising very fast. In fact, I noticed the lowest segment of the kiln was rather cool and the upper ones were warm and eventually hot. That was a bisque firing to 04. The kiln sitter cone tripped the sitter at a decent temp and all works were OK. For the subsequent glaze firing I placed the pyrometer in the middle plug, thinking that perhaps the bottom element wasn't working well. I placed cone 6 cones on all three levels in the kiln. The top cone melted to a proper cone 6 firing, but the middle and lower cones did not. In fact, the bottom cone barely bent. Which kiln model do you have? The model number is listed on the electrical data plate at the bottom of the switch box. Have you tried changing the load density so that less weight is loaded in the bottom and more is loaded toward the top? How did the glaze turn out on the pieces that were loaded near the bottom? Have the cone 6 firings gradually taken more time, or was there a sudden increase in firing time? Sincerely, Arnold Howard Paragon Industries, L.P., Mesquite, Texas USA ahoward@paragonweb.com / www.paragonweb.com Link to comment Share on other sites More sharing options...
neilestrick Posted February 9, 2012 Report Share Posted February 9, 2012 It's possible for each section of the kiln to fire hotter or colder than the rest, depending on how the kiln is loaded. However if the overall firing time is taking longer, I suspect your elements are wearing out, or one is fried. I'd do a visual check on the elements. With the kiln empty, turn them all on high. After 5-10 minutes, carefully crack the lid and see if they are all glowing (it helps if the room lights are off). Keep checking. If all glow, then chances are they are just wearing out and the firings are taking longer as a result. Replace all the elements. If one or more don't glow, then they are burned out or there is a burned out connection somewhere. You'll have to find the culprit and repair as needed. Link to comment Share on other sites More sharing options...
metal and mud Posted February 9, 2012 Author Report Share Posted February 9, 2012 Thanks to the both of your for responding to my forum post. Arnold, the kiln model is A99B, SN 211562. I did about 20 firings last year and had no issues; the last two have taken--suddenly--four hours longer than before. The cone 6 glaze on the top shelf was perfect, as was the pyrometric cone shape. The glaze on the bottom shelves didn't vitrify. I'd read the Paragon owner's manual that I downloaded from the Paragon site, as I didn't have the original owner's manual. I noted that loading the shelves was an important factor, so I moved pieces from the bottom (the cold area) up about six inches. It only held about 10 pieces (it was a refiring). Some of the pieces were quite unhappy at the refiring to 2150 degrees and cracked in half (it's been a tricky clay). I will follow the suggestion about doing an empty firing. How difficult is it to replace the elements? It sounds daunting. It's possible for each section of the kiln to fire hotter or colder than the rest, depending on how the kiln is loaded. However if the overall firing time is taking longer, I suspect your elements are wearing out, or one is fried. I'd do a visual check on the elements. With the kiln empty, turn them all on high. After 5-10 minutes, carefully crack the lid and see if they are all glowing (it helps if the room lights are off). Keep checking. If all glow, then chances are they are just wearing out and the firings are taking longer as a result. Replace all the elements. If one or more don't glow, then they are burned out or there is a burned out connection somewhere. You'll have to find the culprit and repair as needed. Link to comment Share on other sites More sharing options...
Christine Posted February 9, 2012 Report Share Posted February 9, 2012 Hi Experienced Potters-- I was incredibly lucky to run across an old 10-sided Paragon kiln about 18 months ago. (It had been stored in an "old lady's" garage for years.) It's presence in my life got me into pottery and I love it so much I can't remember life without it. Buying a new kiln is out of the question. Would you experienced potters try replacing the elements? Is that hard to do? I'm so unhappy this has happened. I apologize for the length of this post, but I sure would like some advice from you non-newbies out there. This might help Link to comment Share on other sites More sharing options...
metal and mud Posted February 9, 2012 Author Report Share Posted February 9, 2012 I just viewed the video. Thank you for directing me to it! If I do have to replace the element (assuming it's replaceable in my very old kiln) it looks relatively straightforward. Hi Experienced Potters-- I was incredibly lucky to run across an old 10-sided Paragon kiln about 18 months ago. (It had been stored in an "old lady's" garage for years.) It's presence in my life got me into pottery and I love it so much I can't remember life without it. Buying a new kiln is out of the question. Would you experienced potters try replacing the elements? Is that hard to do? I'm so unhappy this has happened. I apologize for the length of this post, but I sure would like some advice from you non-newbies out there. This might help Link to comment Share on other sites More sharing options...
neilestrick Posted February 9, 2012 Report Share Posted February 9, 2012 Anyone can replace elements. Yes, there are tricks of the trade that make it easier and faster, but it general it's not that difficult. I can generally do a full set in 1 1/2 to 2 hours, but I do several a week. Give yourself an afternoon and take your time. My best tip is to only work on one element at a time so you don't get confused by which wire goes where. Keep a notebook by your side to make notes if needed, or label the wires with a piece of tape as you unhook them. It's really just a matter of unhooking the elements from the feeder wires inside the control box, taking out any pins that are holding the element into the grooves, pulling out the element, putting in the new element, and hooking it back up to the feeder wires. The feeder wire to element connection in Paragon kilns is a simple brass connector with a screw on one end that holds the feeder wire, and a set screw on the other end that holds the element in place. The element itself goes through a hole in the center of the terminal. I love those connectors! Paragons don't generally need much in the way of pins to hold them in place like Skutts, since their grooves are so deep, but you may need a pin here and there if the element is being unruly. If you have any broken bricks where the elements can flop out, it's a good time to replace those bricks while the elements are out. If all this seems to scary, contact a local kiln service tech. Your local ceramic supply company can recommend one. Link to comment Share on other sites More sharing options...
Arnold Howard Posted February 9, 2012 Report Share Posted February 9, 2012 Arnold, the kiln model is A99B, SN 211562. I did about 20 firings last year and had no issues; the last two have taken--suddenly--four hours longer than before. Perhaps the voltage is low. That would explain the sudden increase in firing time. This document shows how to test the A-99B elements with an ohmmeter. I don't think an element has burned out, though: http://www.paragonwe...er_Readings.pdf This video shows how to repair a bulging element: Sincerely, Arnold Howard Paragon Industries, L.P., Mesquite, Texas USA ahoward@paragonweb.com / www.paragonweb.com Link to comment Share on other sites More sharing options...
metal and mud Posted February 9, 2012 Author Report Share Posted February 9, 2012 Arnold, the kiln model is A99B, SN 211562. I did about 20 firings last year and had no issues; the last two have taken--suddenly--four hours longer than before. I will check. Thanks. I'm encouraged by the postings that say replacing elements is rather easy, so if that's what's needed, so be it. I'll let you know what the voltage is? Perhaps the voltage is low. That would explain the sudden increase in firing time. This document shows how to test the A-99B elements with an ohmmeter. I don't think an element has burned out, though: http://www.paragonwe...er_Readings.pdf This video shows how to repair a bulging element: Sincerely, Arnold Howard Paragon Industries, L.P., Mesquite, Texas USA ahoward@paragonweb.com / www.paragonweb.com Link to comment Share on other sites More sharing options...
metal and mud Posted February 10, 2012 Author Report Share Posted February 10, 2012 Arnold, the kiln model is A99B, SN 211562. I did about 20 firings last year and had no issues; the last two have taken--suddenly--four hours longer than before. I will check. Thanks. I'm encouraged by the postings that say replacing elements is rather easy, so if that's what's needed, so be it. I'll let you know what the voltage is? Perhaps the voltage is low. That would explain the sudden increase in firing time. This document shows how to test the A-99B elements with an ohmmeter. I don't think an element has burned out, though: http://www.paragonwe...er_Readings.pdf This video shows how to repair a bulging element: Sincerely, Arnold Howard Paragon Industries, L.P., Mesquite, Texas USA ahoward@paragonweb.com / www.paragonweb.com My son and I will do an ohmeter check this weekend. I will get back to you. Thanks again. Link to comment Share on other sites More sharing options...
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