Propane hook up for Olympic 2831 kiln

[MFP]

Hmmmm....the instructions in the manual seem so simple. Not!  The manual says to use a RV low pressure regulator and then just hook a 15 gallon tank up to the kiln. The problem is that the only propane hose that fits both the tank and the firing ring is a hose from Mr Heater that is one inch male on both ends.  All the low pressure regulators are set up to take either a quarter or three eights inch propane hose.....and so far, I have not found an adapter that will convert to attach said hose to the firing ring. It also seems that that size hose would not provide an adequate volume of gas.  I am hoping the Mr Heater hose has some kind of built in regulator.  Any information on how to hook up this ring would be most appreciated!   I currently have it out from under the kiln trying to make sure it works properly before putting the kiln back on top of it! 

 

Marie

[Bill Kielb]

Typical two stage regulator for RV’s are rated at 160,000 btu and generally are 3/8”. To simplify this, How many btu is your kiln rated (nameplate). For that matter what kiln model and maybe post a picture of what you are hooking up.

A barbecue tank is usually 20# and has 4.7 gallons of propane full  and can produce a bit more than 400,000 btu. If your kiln is 100,000 btu per hour, that’s about 4 hours of firing on a barbecue tank.  So 15 gallon may be  a typo, or maybe not. I posted some tank examples below just to give you an idea. Give us name plate, pictures, make, model etc………. this is something likely easily solved but confusing to pick if you have not experienced it before. Folks here can help. This likely is easy and economical using RV style stuff which are mostly 2 stage regulators, which you likely need.

Edited October 15, 2022 by Bill Kielb

[MFP]

In fact, it is a 15 gallon/ 100lb tank as required by the manual.  The kiln is supposed to have 290,000 BTU per hour. I am going to try to send pics. The connection on the firing ring 8s the same diameter as the one on the propane tank which is the same as a five pound tank.

 

[Bill Kielb]

Ok, so there are two pressures we need to address so let’s see if I can describe it so it makes sense.
The pressure needed at the burners has to be approximately 11 “ (INCHES, less than 1/2 psi). Regulators used for this purpose generally have a maximum inlet pressure of 10 psi and reduce it to 11” (Inches). Also the regulator must be capable of supplying  at least 290,000 btu, which means it will likely have a 3/4” diameter or larger outlet size at 11”” of pressure.

Capacity problem

1/2” diameter hose /pipe at 10 psi can easily carry 500,000 btu over many feet of distance

3/4” diameter pipe / hose at 11” of pressure is needed to carry 500,000 btu 10-20 feet

so the usual choice (most economical and lowest pressure for safety) is to hard pipe from the kiln with 3/4” pipe to where the gas bottle will be (within 20 ft of the kiln)  and install a two stage propane regulator at the propane tank.

If we do that we only need ordinary gas pipe from the kiln to the bottle, a two stage regulator (economical) and a flexible connection from the pipe to the second stage regulator (pigtail).

So a quick rough drawing

And some parts, economical regulator (horizontal mount)

 

A safe removable way to connect the regulator to the tank

 

leaving a low pressure short pigtail to connect from the piping to the regulator which need to match 3/4” pipe thread on one end and whatever our regulator outlet thread is, once we pick a regulator.

Edited October 15, 2022 by Bill Kielb

[MFP]

Thanks so very much Bill!

Marie

[MFP]

6 hours ago, Bill Kielb said:

Ok, so there are two pressures we need to address so let’s see if I can describe it so it makes sense.
The pressure needed at the burners has to be approximately 11 “ (INCHES, less than 1/2 psi). Regulators used for this purpose generally have a maximum inlet pressure of 10 psi and reduce it to 11” (Inches). Also the regulator must be capable of supplying  at least 290,000 btu, which means it will likely have a 3/4” diameter or larger outlet size at 11”” of pressure.

Capacity problem

1/2” diameter hose /pipe at 10 psi can easily carry 500,000 btu over many feet of distance

3/4” diameter pipe / hose at 11” of pressure is needed to carry 500,000 btu 10-20 feet

so the usual choice (most economical and lowest pressure for safety) is to hard pipe from the kiln with 3/4” pipe to where the gas bottle will be (within 20 ft of the kiln)  and install a two stage propane regulator at the propane tank.

If we do that we only need ordinary gas pipe from the kiln to the bottle, a two stage regulator (economical) and a flexible connection from the pipe to the second stage regulator (pigtail).

So a quick rough drawing

And some parts, economical regulator (horizontal mount)

 

A safe removable way to connect the regulator to the tank

 

leaving a low pressure short pigtail to connect from the piping to the regulator which need to match 3/4” pipe thread on one end and whatever our regulator outlet thread is, once we pick a regulator.

My problem was being unable to find a flexible hose with those diameters-- the pigtail you show is only 1/4 inch.  The only hose I have found that fits the kiln pipeand the tank is that Mr Heater hose.

[MFP]

Ok, found a propane fittings site and ordered all that you listed. Will let you know how it goes!

[Bill Kielb]

4 hours ago, MFP said:

Ok, found a propane fittings site and ordered all that you listed. Will let you know how it goes!

gas hoses and pressure regulators.com this one is stainless and does require quick disconnect though. Getting all the parts to fit up is usually the issue as this is premium low pressure and the quick disconnect is a great feature but you will need to match up everything for connection which will take a bit of reading and matchup. Mr heater probably does not service large btu loads.we should sketch it out to make sure everything fits end to end really. The regulator pictured will require a 1/2” mpt to 3/4” fpt adapter. Anyway, depending on your regulator we should draw everything out to make sure sizes and gender matchup.

 

 

 

Edited October 16, 2022 by Bill Kielb

[Dave Earley]

I don't understand the variations in pipe sizes for propane mentioned ie. 3/4 " pipe and needle valve. The fitting connecting the tank to a regulator is about 1/8 ".  Venturi burners require small orifices.  Why does 1/2 psi need 3/4 " pipe.

[Bill Kielb]

18 minutes ago, Dave Earley said:

Why does 1/2 psi need 3/4 " pipe.

The size of the pipe required is dependent on operating pressure (11”) equivalent length and how many BTU is necessary to carry. It’s generally easily picked out of a table in a conservative manner. The table below is for low pressure with 0.5” or less pressure drop under full rated flow. In short to ensure 290,000 btu at nearly 11” in the 20 equivalent foot range it needs to be 3/4” ID.

 

Edited October 19, 2022 by Bill Kielb

[Pklove]

Thanks for this Bill,  I’ve been beating my brains out juggling the specs from Olympic (which are only for the later model of this kiln, not what the OP posted pictures of...and mine is older) and the random stuff online.  This helps soooo much.

[MFP]

I just finished getting my propane tank hooked up. I have the older six burner model. I have to test the ring before putting it back under the kiln. I used a propane supply place. I have a high pressure hose that is supposed to deliver the right btus but I am skeptical. Let me know how yours goes. 

You know about putting the 12 inch shelf exactly 1.5 inches under the hole in the lid? For some reason that got omitted from subsequent manuals.  I found out about it from a lady who has fired this model kiln for 40 years. I have the original manual. 

[AJP]

Hi Bill,

You have been so helpful, I'm wondering if you could help me figure out my line for my kiln. Here are the specs. 

BTUS x 1,000:	60
BTU/HR Total:	120,000
Gas Pipe Inside Dim:	3/4"
Propane (LP) Water Column Pressure:	11"
Natural Gas (NG) Water Column Pressure:	7"
No. of Burners:	2
Orifice Size Propane:	3/32
Orifice Size Natural Gas:	1/8
# of Gallons LP per Cone 10 Firing	5

 

I put my questions in all cap. The kiln is the olympic 18 inch torchbearer. I want to use a 20lb propane tank with a flexible line. From reading your above comments I gather I'll need a Qcc fitting handle (DO THEY COME IN ONES FOR 120,000 BTU?). Then a 1/4inch pigtail into a low pressure regulator (WHICH LOW PRESSURE REGULATOR?),  THEN WHAT COMES OUT OF THE REGULATOR TO CONVERT TO 3/4INCH?  I need a 3/4 in propane hose (HOW LONG AND DO YOU RECOMMEND THE ONE YOU RECOMMENDED ABOVE FOR MY KILN?) I will also need an on/off valve  Because I don't have a safety ignition thing (DO YOU RECOMMEND A TYPE OF VALVE?)  
THANKS SO MUCH, I live in a small town and can't find anyone to help.

[Bill Kielb]

5 hours ago, AJP said:

I'm wondering if you could help me figure out my line for my kiln. Here are the specs. 

Yes of course. Can you sketch or describe the kiln location in relation to the propane bottle or even post a picture then we likely can come up with a solution that takes least specialized parts. Sort of a hardware or farm and fleet solution if you will. Then it’s your choice if you want fancy quick disconnects etc…

[AJP]

Hi Bill, thanks! So happy you are still on this chat. Here is a general sketch. The kiln will be portable on wheels and the 20lbs propane tank will be portable too. There are two sketches; one more affordable with smaller diameter flex propane tubing and one  with a more expensive with  3/4 inch flexible tubing. I’d love to go more affordable if possible. Do these sketches Look correct and safe? 

Any chance you can lead me in the direction for online purchase? I need everything circled in pink as well as all the little pipe connections. The kiln has the 3/4 hard pipe off the burners that will need a male connection.

I included a picture of the in line ball valve with regulator (correction: not regulator, but a gauge)  that my friend has in his studio. I can't find this on the internet to purchase.

Thank you so much, It's so confusing trying to find the right stuff to buy online, especially when potential hazards are possible.

 

Edited May 26, 2023 by AJP
used wrong word

[Bill Kielb]

@AJP
I think you have it basically worked out with one observation. Propane tanks carry very high pressure to let’s say 200 psi. The point I need to make is you should have a first stage regulator to go from tank pressure down to 2-10 psi. If it were me I would buy a first stage regulator with the tank fitting, then hose capable to carry the 2-10 Psi to your second stage regulator mounted at the kiln and set for 11 inches of pressure max.. The  built in valve and gauge on your kiln will then allow you to easily adjust while firing.  A hose carrying up to 10 psi can be quite small and carry much more than 120000 btu for more than 20 feet without much pressure drop. It can be easily picked from a table but 3/8” inside diameter is very common and really likely only need to run it in the 2-5 psi range for that small load.  Start setting first stage at 2 psi and make sure you can get 11”” at the kiln and you are good to go. The second stage regulator must be 10 psi regulated down to 11” and rated for 30-70% more than the load or 120,000 btu.  So let’s say a low pressure regulator  11-14” rated in the range of approximately 120,000 - 200,000 btu would be fine. Too large is not better, it won’t regulate as well.

The flexible hose is fine, make sure its rating exceeds 10 psi. Run it as low as you practically can, likely 2 psi or less (the lower the safer) and make sure your second stage regulator is rated at least for your maximum load of 120,000 btu but not so much over rated that it has to make tiny movements to regulate. Remember at 11” on this kiln it’s full blast, so likely you will never really operate it there. Your operation is likely to be in the 0-6” range so you likely will never use the full 120,000. Proper damper management is always critical in any gas kiln btw.

After use, shut off the tank valve, before use, make sure there are no leaks.

A bit about regulators

• First stage regulators. These high pressure regulators adjust for any differences in tank pressure. Technicians install them directly onto a tank, and then the regulator decreases the pressure between that tank and its service line. The purpose of this is to provide inlet pressure of approximately 5 to 10 PSIG to the second stage regulator downstream. This allows smaller diameter service lines to easily supply enough btu’s for the appliance(s).
• Second stage regulators. To adjust pressures between the service line and the appliance, technicians install these regulators outside a building, in your case at your kiln. The low pressure regulators moderate the delivery pressure from the first stage regulator and generate outlet pressure that then flows through to power an appliance. The goal for this equipment is to continue decreasing the pressure in the system to reach safe and appropriate levels for the application, usually an equivalent pressure of about 11″ w.c.

Hope that all makes sense. A small diameter connection at the beginning of the high pressure hose is a local restriction and will not have much effect on output so you should be able to connect your hose to the first stage regulator with whatever diameter adapter is necessary. Typical would be 5/8” on the regulator and you will reduce to 3/8” hose. But just be sure you make this connection with the appropriate fitting for each and it is leak free.

First stage regulators are pretty available and often come with hose and QCC tank fitting. Just referencing your previous post, any ball valve will work, so big box rated for 50-120 psi is just fine. Connect the end of the flex line to your low pressure regulator.

aJust a late add, I picked a maxitrol second stage regulator that should work, along with your pilot safety in the picture. You should be able to google the model # for a supplier. You are looking for the 325-5 series I believe.

 

Edited May 29, 2023 by Bill Kielb

[AJP]

Thanks Bill for all your help. I ended up getting a plumber to help, but learned a lot from you.