What is the cause of this spot on the glass?

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
  • Hope everyone has a wonderful and warm Thanksgiving!
  • Super Cedar firestarters 30% discount Use code Hearth2024 Click here

PDutro

Member
Sep 26, 2021
81
Oregon
RSF Focus 3600. Great fireplace. This spot keeps appearing, any ideas?
[Hearth.com] What is the cause of this spot on the glass?
 
I get that on my gas fireplace so probably not the same as wood issue but it seems to be where there is a bit more air penetrating near the enclosure. If I push on the panel I can see the marking change a bit. I can only see it at certain angles and lighting. So I havent pursued how to resolve.
 
  • Like
Reactions: PDutro