gas fireplace flue

[Chris Hart]

Hi all,
I have attached a photo. It shows two flues. The right side has been modified for a gas fireplace. The left flue has a gas fireplace attached to it but it does not have the same modification. Does the left flue require the same modification or is it ok for the gas fireplace to use the flue as is?
Thanks
Chris

[Bob Harper]

A "gas fireplace" has many meanings. Can you provide make and model of each appliance and the same for those fireplaces they are installed into?
Are they gas logs or inserts? Vented or ventfree? How were the fireplaces modified?

[Chris Hart]

Both units had a wood burning fireplace that has been converted to gas. It is not a gas log. It is a prefabricated gas fireplace. They connected the new fireplace to the orignal metal flue, used with the wood. The right flue (which is the neighbors unit which I did not have access to) was also converted to a gas prefabricated fireplace. The right install also modified the flue by inserting a smaller dimater gas vent stack. I saw this same flue configuration at other neighboring units which is why I am wondering if the unit I was inspecting (the left flue) should be modified in a similar fashion. I do not have any model or manufacturer info. I have already advised my client to get it looked at since many of the neighbors who converted wood to gas have this modification. I am wondering if that modification is actually required. Since both wood and gas produce CO and since the wood burns hotter, the original flue, while maybe not optimal should be safe?

[Bob Harper]

Chris, no offense but I strongly recommend you click on the FIRE Service button on this forum for information on first class training about hearth appliances and venting. A chief duty of the home inspector is to be able to recognize and identify appliances, which will then lead to answers. Until then, about all you can do is to recommend a qualified hearth professional. Typically, factory built fireplaces and gas hearth appliances have very special specific venting requirements and approvals. This is found in the listed installation instructions. In order to locate the correct manual, you must first identify the make and model, then often, too the mfg date code since these appliance often undergo many revisions.
HTH

[Chris Hart]

Will do. Thanks