White Powder residual from a Gas furnace???

[terryrwood]

Sorry for double posting, I relied to a previous post and my comment was buried on page 2.

I have a problem in a home with unvented Gas Heaters, putting off a white powder from the flames, this white powder is pretty annoying it gets on the walls, furniture, tv screen and eventually builds up on the thermopile and the pilot goes out. I've heard people wanting to blame it on leaks in humidifiers and vents, or sheet rock dust, but none of that applies here. they have called it salts but I've see salt residue from water evaporating this is more like baby powder and does not taste like salt, (yea I did) its pretty much tasteless.

In the attached image you can see how thick it builds up where I wiped my finger across deflector above the refractory tiles.

Click to Enlarge

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[Robert Jones]

Is there a humidifier in the home?

[terryrwood]

No humidifier, we felt like humidity was a bit high so we just borrowed a de-humidifier.. Problem with powder has been around for years.

[Jim Katen]

Perfect gas combustion produces only carbon dioxide and water vapor. In a gas furnace, the white powder is a byproduct from the reaction of the water vapor with the metal vent. That's not the case here, because there is no metal vent, just ceramic burners and glazed finishes.

I suspect that the gas is reacting with *something* in the room air to produce the white powder. I have no idea what. However, whatever it is, you're breathing it whenever that thingy is burning.

Just another reason why I don't like unvented appliances.

[Marc]

That flame doesn't look normal to me. If it's concentrated the way it is, it'd be larger. Perhaps the heat from the larger flame is reaching parts that are galvanized. That could cause the white residue.

Marc

[Mike Lamb]

Is this new construction or have you had recent remodeling? Then I would not rule out drywall /construction dust. These appliances like all fuel burning appliance need air for combustion. Dust may be getting sucked out of wall cavities or other places you might not have imagined.

[fyrmnk]

On a side note, you do have a CO detector in the home? Not suggesting that's a problem here, but very important to have nonetheless for when things go wrong.

[mjr6550]

Sorry for double posting, I relied to a previous post and my comment was buried on page 2.

I have a problem in a home with unvented Gas Heaters, putting off a white powder from the flames, this white powder is pretty annoying it gets on the walls, furniture, tv screen and eventually builds up on the thermopile and the pilot goes out. I've heard people wanting to blame it on leaks in humidifiers and vents, or sheet rock dust, but none of that applies here. they have called it salts but I've see salt residue from water evaporating this is more like baby powder and does not taste like salt, (yea I did) its pretty much tasteless.

In the attached image you can see how thick it builds up where I wiped my finger across deflector above the refractory tiles.

Click to Enlarge

70.07 KB

The wording below is from the following link:

http://naturalgasnb.com/cms/en/home/saf ... fault.aspx

You mention that the pilot goes out. It is probably from build-up on the Thermopile, but make sure it is not from the oxygen depletion sensor.

What are the danger signs of carbon monoxide?

Be alert to these signs:

Stale, stuffy air in your home.

The pilot light of your furnace or other gas?fired equipment keeps going out.

A sharp smell of rotten eggs when furnaces and appliances turn on.

A normally clear blue burner flame becomes "lazy" and mostly yellow or pilot light turns mostly yellow. Note that a little yellow will always be present. Small bits of airborne dust will go through the flame causing some yellow.

Chalky, white powder on a chimney or exhaust vent pipe or soot build?up around the exhaust vent.

Excessive moisture on walls or windows in areas with natural gas equipment.

Be sure to check your humidifier settings as well. If the humidifier is turned up too much, this can also cause moisture build up on windows and walls.

Your carbon monoxide alarm sounds

Also, the attachment below is from a gas log installation manual. They mention white powder due to furniture polish, etc.

I see this occasionally (but not nearly that much). I thought it was from impurities in the gas, such as sulfur.

Download Attachment: Doc1.doc

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[Rob Amaral]

Chinese drywall perhaps??

[ShaunMcD]

Hi Terry

Did you ever finalize this matter?

We are experiencing the same problem with our Propane Fueled Gas Fireplace (a Regency)

We had it cleaned & the same issue continues "WHITE DUST" all over the place on a daily basis

Not experienced when we are not using the Gas Fireplace (in the Spring/Summer)

I am concerned for our health due to the ongoing dust.

To complicate matters we have 2 Golden Retrievers (perhaps some Dander is attributed to them), but this does not answers for the white dust/film that gets on the tables, walls, floors, eye glasses etc...

I was hoping you got a solution

Note: We have installed a Portable Honeywell Air Cleaner with a pre-filter & a Hepa filter - The dust still gets all over the place

- Gas Fireplace has been well maintained over the years

- Any help, Comments re- "cause" or a Solution would be appreciated

[Hearthman]

Unless you take samples and have them analyzed by an accredited lab, you're just guessing. Open flame combustion causes a lot of funny things to happen resulting in some interesting things being formed, both gaseous and solid. White residue/ powder is a common occurrence in and around open flames. Since there aren't supposed to be any solid or liquid fuel open flame heating devices in the home, we notice it with gas. Yes, you can get it with those gelled alcohol "fireplace"/ illuminaires and candles, too.

What I typically see the most often in the lab reports I get from samples for Black Particulate Matter (you call it 'soot'), is a witches brew ranging from minerals such as titanium dioxide pigment from white paint to salts to fly ash, skin cells and dust. I wouldn't taste it but that's my preference. I'm not familiar with how acids are supposed to be in powder form as so often quoted but I am familiar with the residues from the reduction of a material by acids. FYI, the trace levels of sulfur in most NG and LPG should not be a consideration in this. The more common carbonic acid and at high temps. oxides of nitrogen would be possibilities including a pinch of nitric acid but it varies.

I'd recommend a rigorous cleaning of the house including wiping down walls. However, as long as you're burning an open flame inside a structure don't be surprised at getting funky residues.

Regarding CO, any signs of CO poisoning are very late, last minute before you die. If a CO alarm listed to UL 2034 alerts, get all occupants to a hospital because the algorithms in those alarms are set to coincide with 10% COHb, which is the medical definition of CO poisoning. Pungent odors can be caused by aldehydes but not CO itself, which has no odor. Signs of venting problems, such as the melted grommets on the top of a scorched water heater should be red flags but never wait for a person to complain of symptoms before suspecting CO poisoning. Those crummy alarms don't protect you from poisoning--they are death alarms. Get an unlisted CO monitor per floor and within 15 ft of each sleeping room.

HTH

[terryrwood]

I'm being told its most likely sulfur burning off from the LPG.

[mlparham]

That flame doesn't look normal to me. If it's concentrated the way it is, it'd be larger. Perhaps the heat from the larger flame is reaching parts that are galvanized. That could cause the white residue.

Marc

I agree with Marc. The flame in the space heater does not look right. I would expect to see the flame covering the entire bottom of the heater. Check the installation directions and the trouble shooting section.

[ShaunMcD]

Perhaps some more pertinent info may help: The Propane Fueled Fireplace is a Direct Vent Fireplace. Other: About 3 years ago we installed a Water Softener & we take this water & put it into a portable humidifier that runs 24/7 during the winter. I am now wondering if what we are experiencing may be related to Softened Water Mist Particles evaporating & settling as the White Powder (perhaps combined with Dog Dander from our two Golden Retrievers) - I do NOT remember experiencing this issue prior to using Softened Water in the Portable Humidifier - ANY thoughts/Comments (or) Experiences along these lines ? PS. All of your comments & replies are very much appreciated (Great Website)

[Bill Kibbel]

Perhaps some more pertinent info may help: The Propane Fueled Fireplace is a Direct Vent Fireplace. Other: About 3 years ago we installed a Water Softener & we take this water & put it into a portable humidifier that runs 24/7 during the winter. I am now wondering if what we are experiencing may be related to Softened Water Mist Particles evaporating & settling as the White Powder (perhaps combined with Dog Dander from our two Golden Retrievers) - I do NOT remember experiencing this issue prior to using Softened Water in the Portable Humidifier - ANY thoughts/Comments (or) Experiences along these lines ? PS. All of your comments & replies are very much appreciated (Great Website)

The white dust syndrome of humidifiers jumped into my head when reading these question but I guess the topic subconsciously kept me silent.

It is quite likely the humidifier. I guess it could be salt from the softener, but is likely some other minerals in your water. Thoroughly clean the humidifier and and go get some distilled water. Let us know if this clears it up.

[Les]

Pretty sure Bill is right. The variable is the softened water. Use distilled water and see what happens.

[Tom Raymond]

It's the humidifier.

If you're not part of the solution, you must be part of the precipitate.

[kurt]

If you're not part of the solution, you must be part of the precipitate.

That's pretty good.

[terryrwood]

I neither have a humidifier, nor a water softener.

[Marc]

If you're not part of the solution, you must be part of the precipitate.

That's pretty good.

Took me a short while to figure it out. It's from high school chemistry.

Marc

[Bill Kibbel]

I neither have a humidifier, nor a water softener.

The recent responses are to a post from ShaunMcD, who does have a humidifier.

The white residue can be made up of many things, but your issue is likely due to byproducts of combustion venting into your home and not outside.

[kurt]

It's from high school chemistry.

Marc

I'm always impressed by a grasp of the fundamentals.

[milkburp]

The white powder is likely Aldehyde.  It's formed by incomplete combustion of the fuel.  If it builds up too much, it can begin to burn with a noticeable odor.  Many people mistake the smell for a "new smell" or material within the enclosure burning off... it's not.  There are 2 things that can reduce the buildup:  reduce the fuel or increase the air in the combustion process.  Neither of these are in your wheelhouse as a consumer or service tech.  These systems are atmospheric in nature, meaning they simply introduce fuel into a natural atmosphere where combustion occurs.  This is a very typical problem with atmospheric combustion including standing pilots.  My gas fireplace also creates this white powder.  We enjoy the yellow flames lapping at the logs (and that's the problem).  A clean burning fireplace would not be very appealing to the eye, think blow torch or furnace power burner.  Simply clean the powder from the effected areas regularly.  A knowledgeable gas provider will give you the same advice.  Also... we aware that when incomplete combustion occurs, NOX related gases are elevated (CO2, CO).  Keep your family protected with quality CO detectors.

[dennispalmer]

White powder residual from gas furnace is basically happen due to the high humidity level. 
 

[Chad Fabry]

Dennis,

 

Please explain why high humidity causes a white powder with gas furnaces.