Gas fireplace Glass Fogged

Was wondering if this is normal? First one I’ve seen like this. Mr. HVAC from next door to the home I was inspection (owner called because I was there) said this is normal and they make a glass cleaner for that. Mr. HVAC installed the HVAC units in this house.

White film on glass panels. According to Mr. Dale W. Feb, Executive Director of the Fireplace Investigation, Research, and Education Service (Moorpark, California), the white film is sulfuric acid. All fossil fuel produces sulfur during the combustion process, and when this sulfur is mixed with moisture, sulfuric acid is created. The white film (acid) may permanently etch the glass and should be removed on a regular basis. Permanent damage might already have occurred to the glass panels and replacement may be necessary. Corrective action:** Consult with a fireplace professional for corrective options**.**** Information obtained from](

It usually happens over the first year or so of use. When the interior components (logs, refractory panels, framing, etc.) are used during the first year “burn in” period, the oils and paints used in the manufacture and curing process will burn off. This can form a white film on the glass. The film can also show up from the burning of dust and dirt that come in with the fresh air supply. All these “fumes” will stick to the condensation that forms when the unit is first started up.

Almost 100% of the units I have seen, once they are cleaned after the first year or so, the film never returns.

You can use a product like “White Off”, designed for this or I also recommend Flitz Paste. It is a polish that I also use on my car. Works great, has no abrasives (so you can use on your headlight covers) and leaves no residue.

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It’s normal and usually easily cleaned. This is how I write it up:

The fireplace had some fog on its inside glass panel, which I recommend cleaning. It is necessary to clean the glass periodically. During initial start-up, condensation, which is normal, forms on the inside of the glass and causes lint, dust and other airborne particles to cling to the glass surface. Also, initial paint curing may deposit a slight film on the glass. All glass should be cleaned after the first 4 to 6 hours of initial burning to remove deposits before they become baked on through further use. After the initial cleaning, glass should be cleaned two or three times during the heating season. For more information, you can go to