Tiny Blue Flames natural gas stove

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earthwindfireplace

New Member
Nov 15, 2013
13
United States
Just moved into a house that has a NG Vermont Castings Radiance (no idea how old, but seems clean).

Starting to get cold this time of year so went through the process of firing it up for the first time. Checked for leaks, fixed a section of dented vent pipe... lit pilot and that stayed on just fine... but once I light the flame I only get a tiny blue flame (turning the adjustment knob only has a very slight effect)

Flame's hard to photograph, but here's a try.
https://www.dropbox.com/s/04arco3zg20qbvr/IMG_20131115_214334.jpg

So I'm a bit perplexed... not enough air?
 
One of our gas wizards is traveling but hopefully another will pop in with advice.
 
Could it be low pressure? Looking at the meter there are four lines - a 3/4" pipe feeds a range and a hot water heater about 35ft away... then there's a dryer right near the meter (5ft) with 1/2" and there's a 1/2" split off of that dryer line running in the opposite direction about 20-25" to the fireplace...

EDIT: Just looked at the lines and did some basic math... shouldn't be the supply...

https://www.dropbox.com/s/x11uhzndu8cl0o3/Screenshot 2013-11-16 12.28.05.png
 
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Try this site and see if you can locate the stove numbers. and the stove manual. scroll down to gas stoves.
http://vermontcastings.com/learn-and-inspire/user-guides-manuals/

Just found the manual in the previous owner's belongings, it's a Vermont Castings Radiance RDV40... seems to be older than the current models they have listed on their site.

The manuals aren't much help - the pilot lights and stays lit, the fire turns on/off, fumes are vented out the wall... no major red flags other than the wimpy flame.

Guess I might just have to pay someone to come out and take a look at my gas pressures, or at least look at my diagram - I've got experience with solid fuel stoves, but a bit of an amateur when it comes to natural gas systems.
 
Just found the manual in the previous owner's belongings, it's a Vermont Castings Radiance RDV40... seems to be older than the current models they have listed on their site.

The manuals aren't much help - the pilot lights and stays lit, the fire turns on/off, fumes are vented out the wall... no major red flags other than the wimpy flame.

Guess I might just have to pay someone to come out and take a look at my gas pressures, or at least look at my diagram - I've got experience with solid fuel stoves, but a bit of an amateur when it comes to natural gas systems.

Do you feel confident enough to remove the burner pan? What you are seeing may just be a blocked gas line. Damned spiders get behind the burner orifice & build a nest that almost completely blocks the flow thru the gas line. That's where I'd look before calling a service tech...
 
Do you feel confident enough to remove the burner pan? What you are seeing may just be a blocked gas line. Damned spiders get behind the burner orifice & build a nest that almost completely blocks the flow thru the gas line. That's where I'd look before calling a service tech...

Yeah , seems simple enough. Is it a matter of cleaning out the orifices themselves? should I remove them? (I think there are two)

Is there any simple way to tell that it's a supply line issue before having the plumber come out and run some new lines? are these the symptoms of low volume?
 
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Yeah , seems simple enough. Is it a matter of cleaning out the orifices themselves? should I remove them? (I think there are two)

Is there any simple way to tell that it's a supply line issue before having the plumber come out and run some new lines? are these the symptoms of low volume?

Yes, but you'll need a manometer. You can tap into the gas port on the front of the gas valve IF there is one. If you don't know, you'd have to post a pic of the front of the valve in order for me to tell...
 
Yes, but you'll need a manometer. You can tap into the gas port on the front of the gas valve IF there is one. If you don't know, you'd have to post a pic of the front of the valve in order for me to tell...
$(KGrHqYOKiQE5FLl154+BO(54RDyb!~~60_35.JPG

I can take a photo of my actual valve if this isn't good enough — but this is the same exact valve. I assume those silver cylinders under the knobs are the ports... or are those adjustment screws?
 
$(KGrHqYOKiQE5FLl154+BO(54RDyb!~~60_35.JPG

I can take a photo of my actual valve if this isn't good enough — but this is the same exact valve. I assume those silver cylinders under the knobs are the ports... or are those adjustment screws?

I can't see the labelling, but if it says PILOT that's the pilot adjustment screw. If it says IN or OUT those are the pressure ports...In will tell you the gas pressure to the valve. Out will tell you the gas pressure to the burner...
 
I can't see the labelling, but if it says PILOT that's the pilot adjustment screw. If it says IN or OUT those are the pressure ports...In will tell you the gas pressure to the valve. Out will tell you the gas pressure to the burner...

Yeah the pilot adj screw is above the electrical contacts on the left there (hard to see in that photo)

Great, so would just about any manifold pressure testing kit work here?

A friend of mine has one of these, for example http://www.amazon.com/gp/product/B0...pf_rd_t=101&pf_rd_p=1630083462&pf_rd_i=507846
 
That'll work just fine...

So this might be one for the record books...

the inlet pressure is fine at about 10 inch WC (acceptable range is 5.5 - 14) - but the pressure at the burner is rated way too high, around 7-9 WC (depending on lo-hi knob adjustment - should be 3.5)... did these knuckleheads run a natural gas line to a stove adapted for LP? Is there something else that would cause this issue?

Might just have to sell this thing in that case, doubt I can still get the conversion kit for a model this old.
 
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So this might be one for the record books...

the inlet pressure is fine at about 10 inch WC (acceptable range is 5.5 - 14) - but the pressure at the burner is rated way too high, around 7-9 WC (depending on lo-hi knob adjustment - should be 3.5)... did these knuckleheads run a natural gas line to a stove adapted for LP? Is there something else that would cause this issue?

Might just have to sell this thing in that case, doubt I can still get the conversion kit for a model this old.

Sounds like it's the regulator. You should be able to get one, since they're made for the valve & not for the stove model...Take the model & serial number off the valve & talk to your local hearth shop or maybe an industrial supply place...
 
Sounds like it's the regulator. You should be able to get one, since they're made for the valve & not for the stove model...Take the model & serial number off the valve & talk to your local hearth shop or maybe an industrial supply place...

Any chance it's been converted for LP use? just wondering because those pressures seem to be pretty close to the rated LP pressures.

I'm guessing if I find the serial numbers and look those up or ask a local hearth shop they'd be able to tell me?
 
Any chance it's been converted for LP use? just wondering because those pressures seem to be pretty close to the rated LP pressures.

I'm guessing if I find the serial numbers and look those up or ask a local hearth shop they'd be able to tell me?

Technically, if your unit was converted by a licensed or certified gas tech, there should be a couple of stickers indicating which kit & the date that it was converted. If it was converted by Joe Homeowner, that may not have happened. Almost all valves are set up for NG from the factory & converted as needed. The serial number will not tell them much, but you can look at the regulator. There should be some numbers or different colored screw heads (Red=LP; Blue = NG)...
 
The owners manual should tell you what the correct orifice size is...Did you pull these orifices off & clean behind them like I suggested above on 17 Nov?

Not a word about orifices in the manual at all — I did remove them and clean them though. I'm stuck on the idea that this is an LP appliance that someone tried to hook up to NG without converting it... going to see if I can get someone in to service it this week to find out for sure.
 
I have the same stove and problem - just a small flame. Just curious as to how you fixed it - our stove was working fine last year and now this winter I have put up with the small flame and little heat out put - time to get it fixed and am trying to do it myself. thanks for any help or directions to point me in
 
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