CONTROLLING A gas burner with cheap ebay PID

[Dawai]

Using a Honeywell Furnace control valve, has the LP kit with the orifice and spring adjustor, this one runs on 24vac to turn on and off, has a thermopile to detect flame, has a pilot light tube, requires a external regulator to reduce incoming gas pressure to 3psi.

HOW IT WORKS, when you turn it to Pilot and depress it flows gas to the pilot burner, once the pilot is lit, the thermocouple- thermopile converts the flame to 50 millivolts and returns the generated electricity to the valve where it "allows" the valve to continue pilot gas and flame. You rotate the blue knob to BURNER. Then when you apply 24 volts to the two terminals, if it has pilot voltage, it turns on the valve, simple and safe.

To connect it to a PID off ebay you use the "relay" contacts, connect a 24vac transformer one leg to the valve, other to the relay in the PID, take the switched leg of the PID relay to the other valve terminal. When the relay makes in the PID calling for "heat" it switches the valve on. THE thermocouple, rtd, or temp sensor from the PID attached in a thermowell in the cook pot, it senses the temperature and turns the valve on and off regulating heat.

THIS one here is tied to a JUNK flame burner from a old hot water heater, to adjust the flame on the unit you take the cap off the "low pressure" adjustment on the Honeywell valve, turn the output pressure up, or down to adjust the flame from the burner, you want a decent flame but not a jet engine sound. USE common sense, too much flame and it "overshoots" the temperature setpoint in the PID control.

Need more help? if I am sitting around I will be glad to talk you through it.

WHO am I? I'm a 56 year old IBEW Electrician-instrument tech from the Chattanooga area with a lifetime of experience, I do not know everything, I am not familiar with everything and things are changing daily. I am a fast study on controls and instrumentation thou. I have a full fab shop here. Am not aging too well thou.

If I had a "WAD of money" and the space I'd have three of these controls, a three pot burner system. If you got a wad of money and need more help than I can provide in emails I can be had, or rented. I'd love to come drink your beer and leave with some of your money.

 

[Dawai]

MORE information,

The Honeywell valve there, you have to put a LP gas orifice into it, and the spring, the lil "screw" that tightens the tension on the spring is the "flame" pressure.. you adjust it till you got a happy flame about the right height. DO Not adjust it to sound like a jet engine, it heats the water so fast it overshoots your setpoint on the PID.. OKAY??

On the burner, there is a "carburetor" there to restrict and adjust the air intake to mix with the gas you are supplying.. you adjust it to give the right color flame, blue, not yellow.

TO turn this valve on you need a "SWITCH" and a "24vac" transformer, if you got more than one valve on your rack you can use the same 24ac transformer and "break" the 24ac through the "PID SWITCH" contacts. That is 24vac to one contact, and the valve on the other, the other terminal on the honeywell valve is the other leg of 24vac, (some valves are dc, read your product information)

The neato thing about these Honeywell valves is "saftey", if the pilot goes out due to a puff of wind or?? it will not throttle open the main burner.

In my closed basement where I have my cooker, I am using electricity. IT needs to be on a GFCI breaker like a "hot tub" for protection. Whereas if any electricity leaks out of the two main hot legs, it shuts off immediately.. so you don't get fried like a french fry.

Have fun, now teach me some more brewing tricks..
David

 

[ClaudiusB]

The neato thing about these Honeywell valves is "saftey", if the pilot goes out due to a puff of wind or?? it will not throttle open the main burner.

David

I use four of the furnace gas valves, Honeywell and White Rogers.

All valves are quick replacement modules with low pressure regulators.





Cheers,
ClaudiusB

 

[pbunt911]

I'd really like to hear more about this setup, not for brewing but for controlling temps in a DIY smoker. My current build uses a tradition resistance heating element, but on a 120v circuit it just barely holds 250F and adding a water pan really does it in. I use this controller:

http://www.auberins.com/index.php?main_page=product_info&cPath=8&products_id=203

Could you tell me the best way to wire this setup? Besides the valve, what else do I need?

Is this valve similar to the one you're using?

https://customer.honeywell.com/en-US/pages/product.aspx?cat=HonECC%20Catalog&pid=VR8200A2132/U#

I've got LOTS of food to smoke so I'm very interested to hear your advice. Thanks!

 

[Dawai]

Hi Buddy.

Too far away for a slab of home smoked bacon? Ha..
Yeah, I know nothing about putting "propane smell" into pork, your burner or?? BUT, I can help you turn the flame on and off.

The valve you have chosen to use, the thermocouple goes into the flame "tip" on the edge to pickup heat and "confirm" there is a flame before turning on the main valve. Your thermocouple-thermopile must be close enough to pick up the heat. Looks like you "need" the proper regulator to reduce pressure.

Wire the 120 volt ac transformer into your "heat plug" in there on your controller, wire the secondary 24vac leg into the valve. WHEN the controller calls for heat, (1) if the pilot light is confirmed to the honeywell valve, (2) if it is switched into flame, then it will flame up with the main valve and turn on the gas and heat.

Setting up the valve to propane, or natural gas is a given. It amounts to a pressure setting and a orifice you change out in the valve.

Tuning the gas flame, well, on most burners there is a carburetor on the end, a silver plate you adjust the air intake with, set your flame height-amount of flow to produce "as much heat as you want" then adjust the carburetor for flame combustion temperature - COLOR.. Okay? not rocket science..

I helped do this once using a "floor heater" from a demo house.. he used the "heat box with burner inside" to heat the cooker with, exhausted the gas out the vent pipe. The twain did not meet.. (you remember the grated floor heaters in homes during WW2 era?) When A child stepped on them, they had blisters looking exactly like the grate. I lived in one of them "rental shotgun houses" in the early-mid 90s. It's valve was a 50mv design that used the thermocouple as the "power source" and needed no 24vac transformer to operate. It'd work when the power was off in the house.
That type of "heater valve" requires a "dry contact" like in a old thermostat or relay.. it only has 50 millivolts to work with generated by the thermocouple-thermopile.

 

[Dawai]

I found my color crayons.. here's you a pictorial example of "what you are going to do, using the "unmodified" controller, adding in a plug in-gas trane valve and regulator and transformer..

Hook that transformer up right, hooking it up backwards will produce pretty blue sparks and smoke and mess up everything it is connected to.

Any furnace style 120-24ac transformer should work, stay away from chinese door bell ones.. they last about 30 minutes.

(yeah, I am gonna "have my fun", don't ya know?)

 

[pbunt911]

Thanks! So just to confirm, I will need:

-a 120v to 24v transformer. This would be wired from the "output" of my PID (a 3-prong 120v outlet) to the valve

-the thermocouple-thermopile - it is used to detect heat from the pilot flame only, correct? This insures the pilot is lit before the main value is opened. The cooking chamber thermocouple would feed into the PID as with any other setup

- pressure regulator - what are the specs of the unit I would need? The valve I'm looking at includes a natural gas to LP conversion kit. Would I need to install this for use with a standard propane tank? Would I then also need to use a regulator?

This is my first DIY project with gas so apologies for what are likely some very basic questions.

Thanks again, this is VERY helpful!!

 

[pbunt911]

Gotcha! I think the drawing nailed it! Thanks again for all your help and I'll let you know how it works!

 

[Dawai]

I did this drawing thinking you were going to continue to use the "smoker" control. PLUG the transformer directly into the "heater" output plug on that. It will turn on the transformer and Gas valve just like it did the heater.. OK??

That is a different drawing for the PID, it has dry contacts you feed the power through like a light switch, take the neutral directly to the transformer, the hot breaks through the contact-switch .. OKAY??? You will have to feed the PID hot and neutral also to power the PID instrument.

 

[ersinemre]

Hi Dawai,

I am developing almost a similiar project. Help needed! Could you contact with me?

Best Regards
Ersin Emre
[email protected]