# Pilot light woes.



## nbolmer

My restaurant has an older challenger range with 8 burners and a griddle. When I purchased the restaurant, most of the burner pilots were out; and as we get close to opening day, I'm concerned, though my cook isn't. 

Do you typically leave your (working) range pilots on overnight?
Do you typically shut off the gas valve to the range overnight?
Do standing range pilots have a safety shutoff where if unlit, they don't leak gas? 
I've heard some chefs prefer to spark the range by hand rather than using the pilots, which saves money.

Note we have LP gas, which is more expensive, as natural isn't available.

Thanks!


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## foodpump

Commercial ranges always have the pilot lights on. 

All commercial ranges that I know of have a thermo-coupler. This is the little device that has a bit sticking out into the pilot light, when it senses heat, it keeps the gas flow going, when it is cold, it shuts off the gas. These devices are fairly cheap, fairly interchangeable and fairly easy to install.


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## kuan

All you have to do is get one burner lit. Then you can

1) Hammer the bottom of a pan on the cast iron grate and create a spark

or

2) Put a large pan on top and "draw" the flame from the burner next to it.

Dang! I'm a good saucier.


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## wereback

Be careful with this though, it could be a _tad_ risky.


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## nbolmer

That makes sense, but I can't seem to locate the thermocouple. My setup looks just like the diagram here: (I tried to post the URL, but you need to have 5 posts before the system lets you. If you google: Wolf Pilot Lights it's the 3, or 4th link down titled "Pilot lights")(the 4 burner setup, twice). It's just a gas line tee'd off to each burner, and a little pilot light at the end of each one. Am I missing something?


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## foodpump

If it's an older model, similar to Wolf, they're probably "Mushroom cap" pilots, as opposed to the "shared" type with two tubes from the pilot leading to two burners. 

With the older "mushroom cap" burners they could be plugged up with crud, or the tiny lines pinched, restricting gas flow, or just plain burned out. 

Most gasfitters/plumbers can put you right fairly quickly, but they will charge. On most ranges there is an access panel on the front face directly underneath the oven, usually about 6" high and running th length of the range, held in place with two screws or with older Wolfs, spring clips. Usually you'll find the model and serial # on this panel, along with the burner btu ratings. Most restaurant supply stores and plumbing stores will carry generic standard thermocouplers and thermostats


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## nbolmer

Yep, it's an old Wolf Challenger, and it has those mushroom cap pilots. So, when one of these pilots go out, there's a factory thermocoupler to keep gas from continuing to come out, or is that an upgrade I need to make?

(thanks for the info! I've had little luck on google with this)


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## oregonyeti

Im a heating and cooling technician, and I held back before but decided to chime in.

There are different "flame proving" devices for a pilot light. Unless your ranges are ancient, there is no need to worry about gas leaking from the pilot lights.

One flame proving device is a thermocouple, another is a thermopile (basically a bunch of thermocouples packed into one piece that makes the output voltage output stronger than a thermocouple) and another is a flame sensor.

If you find a way to manually get gas flowing to the pilot light, and light it, you will have to manually hold the gas on for about 30 seconds -2 minutes so that the flame is "proven" (detected by the control system).

One thing you might check, also, is if the gas nozzles for the pilot lights are clogged (if you can find the nozzles). A wire brush cleaning might clear them, but then once again you will have to manually get the pilot going until the flame is "proven".

If there are thermocouples or thermopiles, they might need a good wire brush cleaning.

If you do look into these things and you still have no luck, it's possible that the gas valves are bad--but my bet would be on clogged pilot nozzles or dirty thermocouple/thermopile/flame sensor..

As far as shutting off the gas at night, there is no need to unless you suspect a leak in the gas plumbing. If you smell gas, ok, but other than that there is no benefit shutting it off.

If you light a pilot and it stays on, good, but if not I'd recommend getting someone experienced to look at it if you've tried those other things.


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## nbolmer

Thanks for the great info-

The pilot light head (mushroom shaped thing) is red with oxidation and cracked on the surface- it looks like a piece of metal that's been in a flame for too long. Tomorrow, I'll remove them and try and clear them out.

Here's the thing -on the pilots that DO work, isn't gas always flowing to them? I know I can manually shut off the entire range at the gasline, or I can individually shut off a pilot with a screwdriver - but when I hold a match to the working pilots, they instantly ignite, and stay ignited. The fact that they instantly ignite (I assumed) meant that gas was coming out of the pilot nozzles at all times, which worried me. 

The advantage to turning the pilots off at night is that I'm only open for dinner during the week, so burning the pilots all day wastes money (each pilot is estimated 10 bucks a month by the gas company, I have 8 burner pilots, another two pilots under the griddle, and 2 in the oven). So I had planned on relighting the pilots when I came into work (except the oven, which I'd leave on- too much hassle) but was worried that gas would be coming out the pilot nozzles all day long, because how else could I instantly light them if gas wasn't coming out. 

I guess the answer is that there's some sort of thermocouple which prevents gas from coming out the nozzle until I hold a flame up to it (?) but I don't see such a device. 

Thanks for all of your help.


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## oregonyeti

My guess is that the working pilots re-light because the thermocouples or thermopiles are still hot and thus still keeping the pilot valve open. They take a while to heat up and they take a while to cool off as well, so they are still being held open by the hot thermocouple/thermopile (my guess). If they are turned off 10 minutes, they cool off and there should be no gas flowing to the pilot when the gas is turned back on.

Cleaning the pilot system parts certainly wouldn't hurt.

Turning the gas off at night will lower your gas expense , yes of course. Those pilot lights probably use 10 bucks each or more, per month. Around here natural gas pilots cost about $15 a month to keep on, and LP more.


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## nbolmer

I've been igniting the pilots with a propane torch, which is very hot. Could that be why they light immediately, even after overnight?


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## oregonyeti

The propane torch probably would not heat up the thermocouple/thermopile in less than 10-15 seconds. It wouldn't be instant.

*clarification* it will light immediately if the pilot gas is manually turned on, but it won't _stay_ on by itself until the thermocouple or thermopile heat up, if that's your flame-proving system. I hope this didn't cause confusion.

At this point I have to bow out and say I don't know enough about your equipment.

If it is a flame sensor setup that would be normal, almost instant "proven flame". That might be the case but I can't tell from here.

I was hoping to give you the answer, but I don't have it without seeing your equipment. Oh well, I tried.


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## foodpump

Sigh.... Yeti, why haven't we met before? Over a beer or two you could have told me that my split a/c unit's air handler requires a _vented _ "P" trap--I found out the hard way--living with dripping condensation water for half a year.

Someone should make it mandatory for every cooking school to have a course or two on the basics of plumbing, heating, gas, especially refrigeration, and electrical work. It's always a, um, "surprise" finding out things the hard way.....


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## psycho chef

The thermocouple is usually only in the oven of the range because it is in an enclosed space where the gas can build up if it blows out. The pilots on the top of the range are always letting gas flow out. Imagine having to press a thermocouple button every time a pilot light got a splash of sauce! I worked on a stove where you used a hand held bbq lighter to lite them _every_ time. The banging the pan to make a spark or making a "bridge" with the pan is only for hard core professional saute guys and should not be attempted by anyone worried about pilot lights. If you dont mind crawling on the floor and removing the oven panel everyday to light the stove, turn the gas off every night. My advice would be to clean the pilots so they flow properly and leave them lit. Ours would almost always blow out every night, but the gas that comes out is not alot, and good ventilation keeps danger minimal. I know it seems like a waste of money, but in the long run you'll see what I mean.


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## nbolmer

Thanks, I couldn't figure out where the thermocouple could possibly be on my range. I think I'll simply turn the screws for the pilots off, and use a welding sparker or some such. Why in the world do commercial ranges not have a piezoelectric sparker.


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## foodpump

No one says you can't put piezo-electric igniters on your range. It's not difficult, just yet another money decision;


If it's an older Wolf Challanger, odds are that the burners are only 17,500BTU's each, to confirm this take a look at the back of the kickplate, the ratings should be stampd/engraved on. Also if the range has been re-configure from nat. gas to any other gas, odds are that the orifices have been exchanged which will further cut back on the btu rating. Most mnfctr's will give this rating on their websites--that is, btu loss when going from nat gas to l. propane or other. 

Most modern ranges start at around 25,000 btu's per burner--quite a bit more firepower when it comes to sauteing, and far better recovery times on the griddle/flat-top and ovens too.

Like I said, it's time to pull out the old calculator and start looking at prices on new equipment.....


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## foodpump

Oh, almost forgot. Every European commercial gas range does have piezo sparkers.

The N. American commercial cooking stuff is kind of like comparing a 350 CI carbeurrated engine to a modern European engine. The standard safety features and design of a typical European fryer made 20 years will still blow the socks off of any new N. American one...


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