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rtockstein 04-04-2012 11:41 AM

need help with propane burner gas valves
 
I've been working on a home brewing system, and I've finally got all the plumbing done, valves hooked up, and ready to go... or so I thought.

It has three 200K btu propane burners. Here's the setup from cylinder to burner:
A 500K btu inlet fitting on my 20lb cylinder. http://www.tejassmokers.com/images/IMG_1194.JPG That is connected to a non-adjustable regulator that is set to 0.4psi and has a capacity of 140K BTU. Then a Brasscraft 24" furnace/boiler gas line. It has a BTU capacity of 130K BTU and is 1/2" ID, I believe. I've got this connected to my main gas line on the rig, which is a 3/4" iron gas pipe. This is where I have 3 branches, one going to each burner. For the valve controlled burners, there is a T that reduces to 3/8" coming off the main line. Then a reducer to 1/4" pipe. This goes into a fixed pressure regulator with 0.5psi output and a 200K btu capacity. This goes directly into the honeywell valve
http://customer.honeywell.com/honeyw...px/VR8200A2132 . It doesn't say it on the sight, but the valve has a max capacity of 200K btu, by adjusting the pressure regulator on the valve. It says this on the box it came in. The outlet (1/2") goes to a 1/2" needle valve, then to the burner. The burner is http://www.tejassmokers.com/newproducts_page6.htm , the 20 jet 200k btu version.

I realize I'm not going to get the 200K btu I want with the gas hose and regulator I've got attached to the cylinder. I just put those on to check for leaks and test out the valves. The burner that isn't controlled by a honeywell valve works fine. It's just 1/2" pipe all the way from the main gas line with a 1/2" needle valve. I think it probably gets somewhere a bit over 100k btu. The valve controlled burners are horrible. Nowhere near enough gas flow. Very lazy yellow flame that I don't think even gets up to 50k btu. Here's a couple problems I've had with the valves. I've turned the pressure regulator screw in the valve all the way up, and it had absolutely no affect. I turned it down, and still no affect. Both burners do this same thing. Also, the pilot light (Q314A model) flames won't adjust either! I turned the pilot light adjustment screw both ways, with no affect. The problem with this is that one of the pilots is wayy to hot, and makes the thermocouple glow bright red.

When I have all 3 burners going at once, they still do exactly as what I described. They don't seem to be diminished at all, even though all 3 are going... the valve controlled flames are still very weak.

You can see in the picture the two on the right (controlled on/off with honeywell valve) that the gas flow is wayyy too low, and the one on the left (no valve, just 1/2" pipe from main to needle valve) is much better.

Is it the regulator or hose on my cylinder, or the gas valves?

So frustrating!!!!!!!!

Thanks for any and all help.

rtockstein 04-04-2012 11:59 AM

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rtockstein 04-04-2012 12:03 PM

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rtockstein 04-04-2012 12:05 PM

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Attachment 48534

TarheelTerp 04-04-2012 12:46 PM

Quote:

Originally Posted by rtockstein (Post 891570)

When I have all 3 burners going at once, they still do exactly as what I described. They don't seem to be diminished at all, even though all 3 are going... the valve controlled flames are still very weak.

I don't see any air shutters at the burner inlet.

rtockstein 04-04-2012 12:49 PM

Quote:

Originally Posted by TarheelTerp (Post 891598)
I don't see any air shutters at the burner inlet.

Those burners weren't designed to have adjustable air shutters. There are small holes in the sides of the base of each jet. The propane flow sucks air in and mixes with the propane. Just like the way a bunsen burner works.

beenthere 04-04-2012 04:34 PM

Did you install the LP conversion kit? Are they LP pilots?

HeatingSolution 04-04-2012 04:35 PM

Were the gas valves in question converted to propane?

rtockstein 04-04-2012 07:27 PM

Quote:

Originally Posted by beenthere (Post 891736)
Did you install the LP conversion kit? Are they LP pilots?

Yes, and yes. I used the LP gas conversion kit 393691. The LP spring is red, and that's the one I put in.

REP 04-04-2012 08:44 PM

To me it is a matter of gas pressure.On the two burners that do not burn correctly I see 3 pressure regulators.One at the tank,one just before the gas valve,and of course the one in the combination gas valve.In order to work correctly the pressure regulators need the proper inlet pressure.
I don't have a conversion chart to look at,but with a monameter instead of a pressure gauge you need to end up with something close to 10 1/2 inches water column or above,and the incoming pressure has to be higher than that.After I checked the orfice sizes at the burner,I would remove the regulator before the gas valve and set the outgoing pressure from the combination gas valve to 10.5 or 11 inches.If the pressures are right and the orfices are right then it should work.
Also I don't get the reduced piping.I don't think you can get 100 btu's out of 1/4 inch pipe.Get rid of that restriction !

rtockstein 04-04-2012 10:28 PM

Quote:

Originally Posted by REP (Post 891877)
To me it is a matter of gas pressure.On the two burners that do not burn correctly I see 3 pressure regulators.One at the tank,one just before the gas valve,and of course the one in the combination gas valve.In order to work correctly the pressure regulators need the proper inlet pressure.
I don't have a conversion chart to look at,but with a monameter instead of a pressure gauge you need to end up with something close to 10 1/2 inches water column or above,and the incoming pressure has to be higher than that.After I checked the orfice sizes at the burner,I would remove the regulator before the gas valve and set the outgoing pressure from the combination gas valve to 10.5 or 11 inches.If the pressures are right and the orfices are right then it should work.
Also I don't get the reduced piping.I don't think you can get 100 btu's out of 1/4 inch pipe.Get rid of that restriction !

Yes, the factory setting on the outlet pressure is 10 in wc, but the MAX inlet pressure is about 13-14 in wc (0.5psi). That's why I have the two regulators just before the valves. Each one of those regulators knocks it down to 0.5psi. The inlet on the regulator is 1/4", so that's why there is a restriction. The reason for the very first regulator that's on the propane tank is because the gas hose's max working pressure is 0.5psi.

With that said, do you think it's possible that the tank regulator isn't allowing enough pressure and flow through that 1/4" restriction to the next regulator? I believe the regulator with the 1/4" inlet is meant to have a higher pressure on that end, so there is a fast enough flow of gas through that small diameter.

Thoughts?

REP 04-04-2012 11:56 PM

Quote:

Originally Posted by rtockstein (Post 891958)
Yes, the factory setting on the outlet pressure is 10 in wc, but the MAX inlet pressure is about 13-14 in wc (0.5psi). That's why I have the two regulators just before the valves. Each one of those regulators knocks it down to 0.5psi. The inlet on the regulator is 1/4", so that's why there is a restriction. The reason for the very first regulator that's on the propane tank is because the gas hose's max working pressure is 0.5psi.

With that said, do you think it's possible that the tank regulator isn't allowing enough pressure and flow through that 1/4" restriction to the next regulator? I believe the regulator with the 1/4" inlet is meant to have a higher pressure on that end, so there is a fast enough flow of gas through that small diameter.

Thoughts?

Again,I see 3 regulators when you don't need all of them.
13 inches is fine for a supply pressure but the gas valve should be the place to knock that down to 10.5 inches to feed the burners.

beenthere 04-05-2012 05:01 AM

Generally, the tank reg for those small tanks knocks the pressure down to 11", so the other regs are just adding restriction.

rtockstein 04-05-2012 07:14 AM

Quote:

Originally Posted by beenthere (Post 892113)
Generally, the tank reg for those small tanks knocks the pressure down to 11", so the other regs are just adding restriction.

Yes, that makes complete sense... I was just discussing that with somebody. I wish I would have thought of that before buying the yellow flex hose and regulator.

What about replacing that hose and regulator with a 0-60psi adjustable regulator?

beenthere 04-05-2012 04:02 PM

Can have to burners with gas valves, and 1 burner with a needle valve on the same set up.


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