Solenoid / Thermocouple / Pilot

[Bru]

Like most who have built a Brutus Im toiling with the huge variety of valves available combined with a shortage of suppliers in my country. To make matters worse prices are horrendous ($300 for the Honeywell) and even the suppliers seem to have virtually no knowledge of their products.

What I need to know is : how does the thermocouple connect to the solenoid ? Are there specially installed connectors in certain solenoids to connect a thermocouple or can all solenoids take a thermocouple ?

Ive been advised to use a "flame failure device" - works using a separate valve installed in the gas line before the solenoid connected to a thermocouple. Is anyone familiar with them ?

Another suggestion is to plumb the pilot light gas line back into the main line thereby eliminating the need for a stand alone pilot light - the burner in effect becomes the pilot light and uses a separate valve to control flow. The advantage being that there is no soot build up and a continuous variable low flame to maintain constant temp better. Can anyone comment ?

 

[Catt22]

I did it the dangerous way using a continuous pilot burner without a thermocouple. The main reason was cost, but also for simplicity:

http://www.iaqwholesale.com/honeywellq314a6102pilotburnerbrlpornaturalgasktip-p-2774.html

Doing it this way does demand that you not leave the burner unattended for safety reasons. I plumbed it to a tee between the solenoid valve and the regulator and equipped it with a needle valve for flame control and shut off.

Using a thermocouple requires a gas valve designed specifically to use one. Not all solenoid valves are equipped this way and most are not. The generic solenoid valves are just that, IOW they are simply electrically operated on/off valves.

I bought this one from Valves4Projects.com: http://cgi.ebay.com/3-8-Electric-So...ater-B21N-/300447718577?pt=LH_DefaultDomain_0

It works perfectly and the price was right. I think you will find that trying to use the burner as it's own pilot will not work very well. If the burner is lit at all, it will likely be producing more heat than you want. Some burners probably won't stay lit at all with such a low gas supply and they may blow out very easily if they do stay lit initially.

Again, the way I'm doing it can be dangerous, so you absolutely must not leave the burner unattended while in operation. I have not had any problems at all, but it only requires one mishap to result in a major disaster. It's much safer to use a thermocouple controlled pilot burner, but as you have learned, it's expensive to do so and very expensive if you do it that way with multiple burners. I only have a single burner under my direct fired mash tun operated with a solenoid valve. The other burner is on my boil kettle which I light manually. My HLT is electrically heated.

I'm not familiar with the "flame failure device", but it must be some type of a thermocouple connected shut off valve.

Kladue is the expert here on this stuff. Perhaps he can help you out with some suggestions.

 

[kladue]

The "flame safety valve" use a thermocouple to generate power for an electromagnet inside the gas safety valve. When the "button" on the safety valve is held down the pilot can be lit and the thermocouple heats up and generates the power to hold the valve open after you release the button. when the pilot goes out the current flow stops and the electromagnet releases the valve and stops the gas flow. A popular brand of the self powered safety valves is BASO, with the H15 and H19 most commonly used. There is a high pressure version made for use on space heaters that run at .8 BAR + pressure, the rest run with pressures lower than 2.8 CM WC. .
An alternative method is the spark ignition method where the flame is detected after pilot ignition and the main gas valve is energized. This setup can be used with 24VAC solenoids and any pressure burner and usually is a bit more expensive to buy new, Ebay is the place for cheaper purchases.

 

[Bru]

Thanks guys.

 

[MNBugeater]

I used the H15s from BASO. It is cheap insurance. Especially when brewing outside. I can't count the number of times my pilots have been blown out and the safety valve stopped the flow of gas. Worth every penny.

 

[Sawdustguy]

Like most who have built a Brutus Im toiling with the huge variety of valves available combined with a shortage of suppliers in my country. To make matters worse prices are horrendous ($300 for the Honeywell) and even the suppliers seem to have virtually no knowledge of their products.

What I need to know is : how does the thermocouple connect to the solenoid ? Are there specially installed connectors in certain solenoids to connect a thermocouple or can all solenoids take a thermocouple ?

Ive been advised to use a "flame failure device" - works using a separate valve installed in the gas line before the solenoid connected to a thermocouple. Is anyone familiar with them ?

Another suggestion is to plumb the pilot light gas line back into the main line thereby eliminating the need for a stand alone pilot light - the burner in effect becomes the pilot light and uses a separate valve to control flow. The advantage being that there is no soot build up and a continuous variable low flame to maintain constant temp better. Can anyone comment ?

For a Honeywell VR8200A look at Figure 7 in The VR8200A Installation Manual. Here in the states, we can get Honeywell VR8200A standing pilot valves off of Ebay for $59.00 US Dollars. The pilot burners are about $14.00 US Dollars.

 

[Bru]

Yeah I know. The trouble is finding a supplier whos prepared to ship to SA.
We get solidly ripped off here.
Ive ended up buying a SCEM valve (paid +-$65) with a flame failure device for my HLT. If a better option comes up (see above)I will consider it for my MLT.
Which US supplier did you use ?

 

[Sawdustguy]

Yeah I know. The trouble is finding a supplier whos prepared to ship to SA.
We get solidly ripped off here.
Ive ended up buying a SCEM valve (paid +-$65) with a flame failure device for my HLT. If a better option comes up (see above)I will consider it for my MLT.
Which US supplier did you use ?

Patroit Supply, here on Long Island in New York. Best of luck with it!