Rex Johnson Posted June 2, 2015 Report Share Posted June 2, 2015 I built a kiln several years ago that's never wanted to get to cone 10. I can fire to cone 5 but it takes some finessing and an extra hour or two, usually 7-8 hours.Set-up:200 gallon propane tank<20 feet of 3/4" pipe between tank and kiln250psi primary regulator at tank to 3/4" pipe10psi secondary regulator between tank and kiln (added by the propane supplier) Two forced air burners using flame retention nozzles.Calculations are I need 400,000 BTU/HR to fire to temperature in appx 7 hours. Caveat - I tee'd off the big kiln to my raku kiln using 20- of 1/2" pipe, that I fire with a Red Dragon 100,000BTU weedburner.This burner has an 18psi regulator. When I use this burner with a 5 gallon propane tank it roars. Works great.However, connected to the new line tee'd off the big tank it's not getting the pressure it needs, just a yellow flame, even turned up all the way with the needle valve.This brought me to think about the 10psi secondary regulator...maybe it's too low a pressure, and maybe this is why the big kiln never fired to temp...???If so, what psi regulator might I need?All speculation at this point, but concrete advise would be welcomed. Link to comment Share on other sites More sharing options...
Rex Johnson Posted June 2, 2015 Author Report Share Posted June 2, 2015 As a note, I've called the porpane supplier. He says it could (maybe) be the 10psi regulator needs adjustment but it should supply more than 600 BTU... He also says he woild have continued with 3/4" pipe for the raku kiln. To me, I can't see that big of loss with the raku torch/burner, because the difference is HUGE. But maybe I'm missing something... Link to comment Share on other sites More sharing options...
Mark C. Posted June 2, 2015 Report Share Posted June 2, 2015 You confuzed me somewhat I think you have 3/4 pipe to a 10 psi reg that goes to big kiln? so if this is the case It could be your regulator-you can adjust most of them easy. What you need is a high volume regulator and easy fix.You need the largest pipe and mpst volume and a high volume regualtor to this kiln. now part two is then you split the line and ran 1/2 another 20 feet (this should be 3/4 pipe as the guy said) thats a long run at laest for natural gas (which is my field of work) 1/2 pipe that long would cut your volume way back-Thats another easy fix to swap out to 3/4. After reading your post could you explain the gas pipe layout-say like 20 feet 3/4 to x kiln with a regulator then tee to 20 more feet to raku kiln in 1/2 pipe??-Most raku kilns do not need much to power them. Mark Link to comment Share on other sites More sharing options...
Rex Johnson Posted June 2, 2015 Author Report Share Posted June 2, 2015 Hmmm... Let's re-do. 200 gallon Propane tank has the primary regulator which reads '250psi" From that we habe appx 20' of 3/4" pipe up to (within 5') the big kiln. At that point there is a secondary regulator that reads '10psi', that was installed by the supplier. I plumbed from that regulator's 3/4" outlet to my two burners. At the tee to these burners it's reduced to 1/2" respectively both sides. Now, so that I don't have to bring in 5 gallon propane tanks every weekend I figured, why not plumb out to the raku kiln from the big tank/big kiln. I tee'd off the existing 1/2" burner pipe out 20+" to the raku kiln. The 100K BTU raku burner has an 18psi regulator, which when attached to a 5 gallon propane tank works very well, (roaring blue flame). But when attached to the 1/2" pipe only heats to a low yellow flame. This leads me to think that since only 10psi is getting to the torch via the secondary regulator, the torch isn't getting the psi it requires. Granted, it may be that there is a (some) pressure drop due to the pipe length and possibly the size as well. However, the raku burner flame is dramatically reduced. So, before I decide to buy all new pipe... Today I'm going to attached the raku burner right up next to the big kiln burner at the 1/2" tee, eliminating the length of pipe going to the raku kiln. If I'm correct about the 10psi secongdary regulator, it should burn about the same. If I'm wrong I guess I'll find out. Link to comment Share on other sites More sharing options...
Rex Johnson Posted June 2, 2015 Author Report Share Posted June 2, 2015 What you need is a high volume regulator and easy fix By high volume do you mean a regulator that's like 20-30psi? This is exactly what I'm thinking. Before I argue with the propane guy I want to know for sure I'm correct... Link to comment Share on other sites More sharing options...
Mark C. Posted June 3, 2015 Report Share Posted June 3, 2015 Its not PSI it's volume or capacity. There has been a bit written on this before You may want to search for it. Mark This thread covered it in depth http://community.ceramicartsdaily.org/topic/6039-real-time-kiln-advice-kiln-curently-firing/page-4?hl=%2Bpressure+%2Bregulator&do=findComment&comment=59083 Link to comment Share on other sites More sharing options...
Rex Johnson Posted June 3, 2015 Author Report Share Posted June 3, 2015 I tested the raku burner right at the big kiln eliminating all the tee'd in 20+' of length to the raku kiln. As I figured the burner is still a weak yellow flame. So the 1/2" length of pipe is not the culprit as far as the raku kiln goes. So, volume not psi, I'm not sure I understand the concept. 10psi secondary regulator is what's installed, what is it I need? Forgive my lack of knowledge. Link to comment Share on other sites More sharing options...
Rex Johnson Posted June 3, 2015 Author Report Share Posted June 3, 2015 Would this be what I'm looking for ? 1,000,000 btu/hr Second Stage Regulator w/Rear Discharge http://m.protanksupply.com/regulators-detail.asp?prodID=2077 A full size second stage regulator design perfect for higher BTU applications. It features an adjustable range from 8-14" WC (factory set @ 11" WC), stainless steel internal components, fluorocarbon (FKM) seat discs, molded lip fabric reinforced diaphragms and large aluminum precision machined orifices providing superior downstream regulation and maximum corrosion resistance against weather or contaminated gas. Has a rear discharge back mount outlet for convenient wall mount applications. Link to comment Share on other sites More sharing options...
Rex Johnson Posted June 3, 2015 Author Report Share Posted June 3, 2015 Inlet: 3/4" FNPT Outlet: 3/4" FNPT BTU/hr: 1000000 Pressure: 11" WC Link to comment Share on other sites More sharing options...
Mark C. Posted June 3, 2015 Report Share Posted June 3, 2015 Since I'm Not a propane guy I suggest calling Mark Ward http://www.wardburner.com/ He is the expert on this Get his advice on what the specs you need for the right regulator-pressure (PSI) and Volume and BTUs otherwise you are just guessing You should also have the specs from your forced air burners for him. Mark Link to comment Share on other sites More sharing options...
Rex Johnson Posted June 3, 2015 Author Report Share Posted June 3, 2015 Yes, I'm thinking about calling, but I'm pretty sure he's hard to get a hold of. I e-mailed him and got the form letter back today. Link to comment Share on other sites More sharing options...
David Woodin Posted June 3, 2015 Report Share Posted June 3, 2015 The secondary regulator at 10 psi would than need a regulator for the burners set at 11 " W.C. at least that is what powered burners for kilns usually use. Mark Ward is the one that can help on this. David Link to comment Share on other sites More sharing options...
oldlady Posted June 3, 2015 Report Share Posted June 3, 2015 my post to call marc ward got lost in the "you did not hit post" memory failure. he is a very kind man who will help you, do not assume. Link to comment Share on other sites More sharing options...
Rex Johnson Posted June 4, 2015 Author Report Share Posted June 4, 2015 At this point I've given up on hooking the Red Dragon up to the main line. I'll just have to use the 5 gal bottles.As far as the big kiln, I took a closer look at the secondary reg yesterday. I should have done this before posting I guess...It's rated at 1,400,000 BTUs.fisher r622-dff(low pressure regulatorSo I assume it's got enough volume.When Mr Propane Guy comes out I'm still going to have him test the line and regulators. product name:fisher r622-dff(low pressure regulator) inlet pressure:10psi (0.7kg/cm^2) outlet pressure range: 0.3~0.46psig (22~32mbar) inlet & outlet connections: 3/4" fnpt capacity btu/hr propane: 1,400,000 Link to comment Share on other sites More sharing options...
Mark C. Posted June 5, 2015 Report Share Posted June 5, 2015 To adjust that just unscrew the black plastic top off and you will see a screw slot on the top -thats how you adjust it.In and out for more or less. Mark Link to comment Share on other sites More sharing options...
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