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Author Topic: What does my boiler's pilot light flame change colour?  (Read 9155 times)

Offline virginiajim

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The pilot light on the heater in my bathroom changes color that at first I thought indicated faulty equipment or contaminated fuel.  It turns out that the color change occurred only when an ultrasonic humidifier in the next room was running.  The humidifier uses tap water from a well that contains alkaline or soft water.  The photos below show a normal blue flame and one colored by the minerals from the humidifier[http://i596.photobucket.com/albums/tt50/virginiajim/flameandnominerals.jpg][http://i596.photobucket.com/albums/tt50/virginiajim/flameandminerals.jpg]
« Last Edit: 05/02/2009 17:28:35 by chris »


 

Offline virginiajim

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Re: What does my boiler's pilot light flame change colour?
« Reply #1 on: 04/02/2009 19:49:38 »
The pilot light on the heater in my bathroom changes color that at first I thought indicated faulty equipment or contaminated fuel.  It turns out that the color change occurred only when an ultrasonic humidifier in the next room was running.  The humidifier uses tap water from a well that contains alkaline or soft water.  The photos below show a normal blue flame and one colored by the minerals from the humidifier.

 

Offline virginiajim

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Re: What does my boiler's pilot light flame change colour?
« Reply #2 on: 04/02/2009 19:53:14 »
The pilot light on the heater in my bathroom changes color that at first I thought indicated faulty equipment or contaminated fuel.  It turns out that the color change occurred only when an ultrasonic humidifier in the next room was running.  The humidifier uses tap water from a well that contains alkaline or soft water.  The photos below show a normal blue flame and one colored by the minerals from the humidifier. 8)
 

Offline lancenti

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Re: What does my boiler's pilot light flame change colour?
« Reply #3 on: 05/02/2009 01:26:29 »
I would say that it is caused by minerals in the air burning up. To identify what exactly it is, you can use this link:

http://webmineral.com/help/FlameTest.shtml
 

Offline lightarrow

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Re: What does my boiler's pilot light flame change colour?
« Reply #4 on: 05/02/2009 08:00:47 »
The pilot light on the heater in my bathroom changes color that at first I thought indicated faulty equipment or contaminated fuel.  It turns out that the color change occurred only when an ultrasonic humidifier in the next room was running.  The humidifier uses tap water from a well that contains alkaline or soft water.  The photos below show a normal blue flame and one colored by the minerals from the humidifier. 8)
It's very normal. A flame is very sensitive to little amounts of chemicals in the air. The colour seems to indicate the presence of sodium and calcium (common chemicals in water).
« Last Edit: 05/02/2009 08:02:34 by lightarrow »
 

lyner

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Re: What does my boiler's pilot light flame change colour?
« Reply #5 on: 05/02/2009 13:30:07 »
Colouration of a flame could be due to dirt on the burner. If you knock a gas ring, the flame goes coloured. Is there any vibration due to the motor running, which could do the same thing.
For the flame to be coloured due to the overall content of the air I should have thought that you would actually smell the difference in air quality. The only thing which you wouldn't smell would be the water vapour. Could the change in humidity account for it.
I suggest that you turn off the humidifier and observe the flame. If it changes quickly then the effect is mechanical, if it changes slowly then it could be chemical. Then, boil a kettle nearby and see if you get the same effect from humidity alone; eliminate the humidifier as a special factor if you can.
That should keep you busy  one Sunday afternoon - enjoy and come back with the experimental results. We can then B/S some more!
 

Offline RD

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Re: What does my boiler's pilot light flame change colour?
« Reply #6 on: 05/02/2009 15:48:48 »
Quote
Colors of Elements in a Flame
Aqueous solutions of various compounds are sprayed into a Meeker burner flame from an atomizer.
 The flame colors are demonstrated close up...
http://jchemed.chem.wisc.edu/jcesoft/cca/cca2/MAIN/FLAME/CD2R1.HTM
 

Offline Bored chemist

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pilot light flame color changes
« Reply #7 on: 05/02/2009 17:30:52 »
Congratulations, you have accidentally discovered the idea behind the flame emission spectrometer- even down to the relatively recent idea of using ultrasonic nebulisation to add the analyte.

Inncidentally it's impossible to accurately judge the elements present from the picture on a PC or TV screen but my money is on sodium which gives a yellow flame even when only tiny traces of sodium are present.
 

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pilot light flame color changes
« Reply #7 on: 05/02/2009 17:30:52 »

 

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