lukeseall Posted March 11, 2019 Report Share Posted March 11, 2019 I was wondering if someone could cast an experienced eye over these elements for me and tell me if you think they need replacing? I suspect they do as my kiln struggles over 1100 degC. Not really sure what to look for in a knackered element though. Is it sensible to replace all elements at once? Or is it possible that some wear out faster than others and you don't always need to replace them all in one go? Thanks Luke Link to comment Share on other sites More sharing options...
liambesaw Posted March 11, 2019 Report Share Posted March 11, 2019 Find out the "new" element resistance and compare it with the resistance you're getting from these older ones. I don't know that looking at pictures would tell us the whole story. Link to comment Share on other sites More sharing options...
neilestrick Posted March 11, 2019 Report Share Posted March 11, 2019 They don't look all that bad, but check their resistance to make sure. You may also have a break in one and that's what's making it fire slow. What's the max temp of the kiln? Link to comment Share on other sites More sharing options...
oldlady Posted March 11, 2019 Report Share Posted March 11, 2019 neil, the darker photo seems to have a different weight of wire elements. do you think only one was changed out in the past? is it important to buy the correct brand for your kiln? Link to comment Share on other sites More sharing options...
liambesaw Posted March 11, 2019 Report Share Posted March 11, 2019 2 minutes ago, oldlady said: neil, the darker photo seems to have a different weight of wire elements. do you think only one was changed out in the past? is it important to buy the correct brand for your kiln? My kiln is similar, it has heavy wire in the middle elements with wider loops. And tighter smaller gauge in the top and bottom, I think it's for more even heating in smaller kilns? Link to comment Share on other sites More sharing options...
neilestrick Posted March 11, 2019 Report Share Posted March 11, 2019 @oldlady In a lot of single zone kilns (1 thermocouple) they run different (hotter) elements in the very top and very bottom to compensate for heat loss out the floor and lid. I'm assuming that's what going on here, but it's hard to tell from the photos since we can't see how many rings/elements there are. Link to comment Share on other sites More sharing options...
oldlady Posted March 12, 2019 Report Share Posted March 12, 2019 thank you both. Link to comment Share on other sites More sharing options...
Bill Kielb Posted March 12, 2019 Report Share Posted March 12, 2019 Measuring this (resistance) is the best way to know. I believe Neil has quoted 10% change (cold) is time for replacement. I recently had the opportunity to see what that translated into at top temperature so here goes. A recent set of elements that were measured worn by about 15% cold translated into about 30% less energy at the top temperature so that particular kiln struggled to make cone six (fast glaze) in 14 hours. After complete element replacement the normal fast glaze schedule returned to six hours give or take a little. pretty dramatic difference actually. The kiln pictured below has more than 1200 firings on it and received the new elements. Link to comment Share on other sites More sharing options...
lukeseall Posted March 12, 2019 Author Report Share Posted March 12, 2019 Thanks all. Have asked the kiln manufacturer for resistance values and will get the multimeter out tonight! Link to comment Share on other sites More sharing options...
Bill Kielb Posted March 13, 2019 Report Share Posted March 13, 2019 Power off reminder and if the elements are in parallel you will be reading the combination of the two which is the reciprocal sum so if it seems off, measure them separately. We are talkin small values and differences of one to two ohms typically. 2000 - 4000 watts nets about ten ohms for a combination of two elements in parallel or 20 ohms each. 10% change in each element turns into two 22 ohm elements but in parallel measure 11 ohms. The point of this? Go in realizing the numeric change is going to likely be small so careful measurement and measure individually (disconnected from each other) if you are not familiar with parallel and series circuits. Link to comment Share on other sites More sharing options...
lukeseall Posted March 13, 2019 Author Report Share Posted March 13, 2019 Thanks Bill. I sort of know what you mean. Assuming my readings are accurate then the elements have between 10% and 16% increase in ohms. Which means I need some new ones I guess. Link to comment Share on other sites More sharing options...
Bill Kielb Posted March 13, 2019 Report Share Posted March 13, 2019 Yes you do for sure. Likely Slow firing until then whether you want to or not. Good job testing! Link to comment Share on other sites More sharing options...
lukeseall Posted March 13, 2019 Author Report Share Posted March 13, 2019 Well thanks for helping me get to the answer. I'll probably have to start a new thread when it comes to fitting them! Link to comment Share on other sites More sharing options...
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