Pilot light question

[Richard]

We've got a ventless fireplace. I use a 100 lb tank outside. In the spring, I move the tank away from the house (eyesore for the wife) and put it in the woods with some other stored things.

I have to wrap up the connections that screw into the tank or the bugs will build a home inside the tubes.

Come along fall, I reconnect everything BUT.... over the prior 6 months, virtually all the propane that has been in the line has disappated.

What happens is I connect the tank back to the line, open it up. The line is full of air and then gets put under pressure when the propane line opens.

I go inside and have to purge a lot of this air before I can get my pilot light lit. It can take 10/20 minutes of fiddling before I can get it lit. Once I get it lit I never have this problem for the rest of the season. I might add that we do not leave the pilot light on, we kill it 100% and have to relight it every time we use fireplace. We do this by choice to simply not burn up gas with the pilot light. The fireplace gas supply is turned 'off' during this down time.

Here's my question: When I'm trying to purge the air from the line is the air slowly purging if I simply push & hold the pilot button in or do I need to push/release/push/release the button?

If I can simply hold it in.... it seems I'd have to hold it for 10/15 minutes.

Is there a different way to purge the air out of the gas line leading from outdoors to the fireplace?

I might add.... this is currently a moot point since I went through this last night but it drove me nuts having to fiddle with it that I finally decided I'd ask.

 

[MossRoad]

I think you have to hold the button in to bypass the thermocouple. That closes when it is cold... I.E. your pilot light goes out, and shuts off the gas supply. My guess would be you have to hold it in until the air bleeds out, you can light the pilot, and then heat the thermocouple. But that is just a guess.

 

[swiftboot]

Not sure if your fireplace would be the same but,,,,I use a propane fryolator (for french firies etc) and it does the same thing when i first turn on the gas. I have found if you turn the gas on and wait 20 mins or so and then light normally it takes away alot of the hassle. I do not have to hold the valve down during this time. It does make sense that gas wouldnt flow thru the line if the valve wasnt depressed as in lighting the pilot light, but apparently just enough does to fill the line enough to lite the pilot light after the 20 min wait. Try it anyway and see what happens. chuck

 

[Bird]

I agree with both of the other posts. You have to hold the button in to purge the air out of the line, however, if you turn the gas on and don't try to purge the air, after awhile the gas and the air in the line will mix enough that you can light the pilot without waiting to bleed off the air. At least that's been my experience with propane appliances.

 

[dave1949]

I don't remember if propane is heavier or lighter than air, its one or the other and will probably affect the mixing Bird mentioned. With different arrangements of tank, piping and height of appliance compared to the tank, I would expect different results.

I vote for holding in the button for a while if it won't light after being connected for 20-30 mins. - while you enjoy a cold beverage of your choice.

Dave.

 

[Western]

Not much to add here, but I would try to find a way to leave the tank in place. Camouflage, paint,rock, something..

 

[Mgrove]

Propane is heavier than air. It tends to run into floor drains and causing problems later. If you can get to the pilot assy, you could heat the thermocouple with a blow torch, then release the button and turn the valve to on. BE SURE TO KEEP THE TORCH ON THE THERMOCOUPLE WHILE DOING THIS. iT'S NOT AS DANGEROUS AS IT SOUNDS, JUST KEEP THE TORCH ON THE THERMOCOUPLE until the burner lights. Boy am I going to get it for posting this.
Max

 

[Bird]

Yep, natural gas is lighter than air, and LPG is heavier than air.

 

[tommu56]

Put a valve on the house end and close it before closing the tank valve then disconnect and move tank.
Look for a horizontal 100 and put some shrubs in front of it and leave it hooked up.

tom

 

[MossRoad]

Propane is heavier than air. It tends to run into floor drains and causing problems later. If you can get to the pilot assy, you could heat the thermocouple with a blow torch, then release the button and turn the valve to on. BE SURE TO KEEP THE TORCH ON THE THERMOCOUPLE WHILE DOING THIS. iT'S NOT AS DANGEROUS AS IT SOUNDS, JUST KEEP THE TORCH ON THE THERMOCOUPLE until the burner lights. Boy am I going to get it for posting this.
Max

I thought about that, too, but didn't want to say it.

 

[2manyrocks]

The thermocouple is a safety device. It is intended to keep gas from flowing out in your house if there's no flame at the burner. If you don't heat the thermocouple when starting your pilot light, the gas isn't supposed to flow through it.

 

[schmism]

The thermocouple is a safety device. It is intended to keep gas from flowing out in your house if there's no flame at the burner. If you don't heat the thermocouple when starting your pilot light, the gas isn't supposed to flow through it.

yes thats what the little red button is for. to bypass the thermocouple.

so when you hold the red button down (yes you have to hold it down continuously) you only open the pilot light valve. so the air only leaks out at a slow rate. (the rate it takes to keep the pilot light lit)


the torch method thats mentioned does 2 things. 1) it heats the thermocouple so that it opens the "big valve" 2) it acts as the pilot light to lite the gas coming from the "big valve"

as soon as the pilot light is lit and has warmed the thermocouple for a few seconds (10-15) you can let go of the red button. if your actively calling for heat (at that moment), then the big valve will be open (due to the warm thermocouple) and as soon as you let go of the red button the larger burner will kick on.

 

[Travelover]

Propane is heavier than air. It tends to run into floor drains and causing problems later. If you can get to the pilot assy, you could heat the thermocouple with a blow torch, then release the button and turn the valve to on. BE SURE TO KEEP THE TORCH ON THE THERMOCOUPLE WHILE DOING THIS. iT'S NOT AS DANGEROUS AS IT SOUNDS, JUST KEEP THE TORCH ON THE THERMOCOUPLE until the burner lights. Boy am I going to get it for posting this.
Max

I used to use this technique with my old gas furnace every fall when I re-lit the pilot. Once the main burner lights, it pulls out all the air from the lines as the gas rushes to the burner. Once it is shut off, it resorts to normal operation and the pilot stays lit. Maybe I'm missing something, but I don't see the downside.

 

[Richard]

so when you hold the red button down (yes you have to hold it down continuously) you only open the pilot light valve. so the air only leaks out at a slow rate. (the rate it takes to keep the pilot light lit)


the torch method thats mentioned does 2 things. 1) it heats the thermocouple so that it opens the "big valve" 2) it acts as the pilot light to lite the gas coming from the "big valve"

as soon as the pilot light is lit and has warmed the thermocouple for a few seconds (10-15) you can let go of the red button. if your actively calling for heat (at that moment), then the big valve will be open (due to the warm thermocouple) and as soon as you let go of the red button the larger burner will kick on.

Hmmm....

I think I'm finally getting something here.

For the record, my button isn't red it's the same knob used to turn/adjust the gas burners. The first position allows it to be depressed for the pilot and it can not be 'turned up' any further while depressed.


So, unless that fact changes anything.... let me reword this into my ignorance and see if I'm understanding this.


Currently: If I push/hold my pilot button.... it will take "X" minutes for the air to dribble out through the pilot circuit. This specifically lets air/gas seep through at a VERY slow rate.

If instead, I push the pilot button in while holding a flame (butane lighter for fireplace work ok?? is that a 'torch' or do I need my MAP gas? )

Anyways...if I hold a flame to the thermocouple (and I'm not sure exactly where that is) then heating the thermocouple will allow the "secondary" valve to open and perhaps allow the gas (air) to purge much more quickly through the system.


Side question....

Presuming I am grasping the above... then THANKS!!

If however, my knob is creating a situation by being locked in the pilot location when depressed.... would that defeat the secondary volume logic?

If it would.... could I simply turn the gas on while heating this thermocouple and (hopefully) that would allow the main gas to come on, totally bypassing the logic of lighting the pilot light?

(does that even make sense?)

 

[johnk]

There goes a pair of eyebrows. If you don't know what you're doing don't mess with trying to purge lines that way. It'll only get you burned. I have 40 yrs w/ a utlity and I see the new guys getting singed all the time trying to spike valves open and faulty safety devices.. Be careful. If you don't know what you're doing don't do it..Just my opinion.

 

[MikeD74T]

I also use the Mgrove method every fall. My propane torch burns at the same temp as the main burner so perfectly duplicates the pilot. Have never had anything other than a normal ignition of the main burner.

johnk, Do you work in the field or the office? Does your company not train it's field techs sufficiently? Miked74T

 

[johnk]

I work in the field. I work with natural gas and do the service calls in residential and commercial properties for gas leaks etc. In my company 90% of the old work force left last year at contract time so many ions of experience were lost and threr really isn't the manpower to train all the new guys because the bosses themselves are in their 20's and early 30's w/ hardly any knowledge except from the book of what the heck is going on. I can retire at any time but want to get a little closer to that 62 age.. You know what happened to all the 401's so I'm kind of glad i didn't leave last contract ...