Installing a DV vent gas insert in a Majestic MBU36

  • 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.

pennstateee

New Member
Oct 6, 2021
4
West Chester PA
My new house has a Majestic MBU36 ZC fire place that was installed when the house was built in 1997. It currently have a gas log set installed. I would like to install a direct vent insert. The local Mendota/ Lopi dealer informs he has nothing that will fit in the MBU36. I have spoke to the local Kozy Heat dealer and the Chaska 29 insert looks like a good possibility. Does anyone have experience installing a gas insert in a Majestic MBU36? I reviewed the Chaska 29 insert documentation: “Any smoke shelves, shields, and baffles may be removed if attached by mechanical fasteners. If necessary, remove firebrick to obtain at least the minimum opening requirements.” Any thoughts on this?
 
Does the Majestic MBU36 ZC Manual indicate that modifications for a gas FP insert is acceptable in this box?
Many manufacturers disallow such mods, & your homeowners insurance co. make take issues with what you
want to do...
 
On page 13 of the installation manual it does state that " The Majestic MBU Series is fireplace is designed to accept a 1/2 gas line for an approved gas appliance."
 
That's a start. They may be referring to a gas log set instead of an insert.
You should still check with your insurance carrier.
You might want to have a chat with someone from the building dept. as well...
 
Would it be better if we installed a Majestic ruby series insert in the Majestic MBU 36? From the ruby series installation manual.
"For Installation into a Zero Clearance Wood burning fireplace: • The brick (refractory), glass doors, screen rails, screen mesh and log grates can be removed from a factory built firebox in order to gain minimum gas insert opening requirements. • Any smoke shelves, shields and baffles may be removed from the factory built firebox if attached with mechanical fasteners."

We would have a Majestic insert in an Majestic fireplace.
Thank you for your help and insights!
 
On page 13 of the installation manual it does state that " The Majestic MBU Series is fireplace is designed to accept a 1/2 gas line for an approved gas appliance."
Page 3 clearly says do not install a fireplace insert. Not really any way around that
 
  • Like
Reactions: DAKSY
Thanks you for the great information. I will not get an insert. The old log set is hard to start. I think it is 20 years old. Should I have this serviced or have it replaced?
 
Thanks you for the great information. I will not get an insert. The old log set is hard to start. I think it is 20 years old. Should I have this serviced or have it replaced?
There is no way for us to know the right answer to that without being there
 
Page 3 clearly says do not install a fireplace insert. Not really any way around that
That is not what is says I just read it. It says do not install a fireplace insert that is not specified for this fireplace. Or something similar to that. Some gas fireplace inserts specify what they are tested and approved to be installed into. Maybe a year ago on another thread we debated this topic. So I know not everyone on this forum agrees. I see inserts installed in zc fireplaces all the time usually the 42" model fireplaces. There are some smaller bvent gas inserts also that may work.
 
That is not what is says I just read it. It says do not install a fireplace insert that is not specified for this fireplace. Or something similar to that. Some gas fireplace inserts specify what they are tested and approved to be installed into. Maybe a year ago on another thread we debated this topic. So I know not everyone on this forum agrees. I see inserts installed in zc fireplaces all the time usually the 42" model fireplaces. There are some smaller bvent gas inserts also that may work.
Read it again. It says fireplace inserts OR components that are not specified for use with this fireplace.

It isn't allowed it doesn't matter what people here agree upon. It matters what the instructions say.
 
Read it again. It says fireplace inserts OR components that are not specified for use with this fireplace.

It isn't allowed it doesn't matter what people here agree upon. It matters what the instructions say.
Right. So if the gas insert manufacturer has their product tested and listed for use in a manufactured zc fireplace, your assertion is that it is not allowed because it was listed by the zc manufacturer? This makes no sense as most gas inserts were designed and listed after the zc fireplace was manufactured. And it's definitely not what happens in common practice. So your telling me you will not install a gas insert into a zc fireplace if that exact model gas insert is not listed for use by the zc fireplace? (Even if the gas insert is listed for use in a zc fireplace).
 
Right. So if the gas insert manufacturer has their product tested and listed for use in a manufactured zc fireplace, your assertion is that it is not allowed because it was listed by the zc manufacturer? This makes no sense as most gas inserts were designed and listed after the zc fireplace was manufactured. And it's definitely not what happens in common practice. So your telling me you will not install a gas insert into a zc fireplace if that exact model gas insert is not listed for use by the zc fireplace? (Even if the gas insert is listed for use in a zc fireplace).
I am telling you I will not install any insert in a fireplace that says you can't install inserts in it.
It doesn't matter what the insert manufacturer says both sets of instructions have to allow it. And yes the only way this is allowed is in that specific insert was tested in that specific fireplace.
 
I am telling you I will not install any insert in a fireplace that says you can't install inserts in it.
It doesn't matter what the insert manufacturer says both sets of instructions have to allow it. And yes the only way this is allowed is in that specific insert was tested in that specific fireplace.
Right.... But the manual does not say you can't install inserts into it. It says "Do not install a fireplace insert or other products not SPECIFIED for use with this fireplace". So who specifies? Some gas insert manufacturers specify. I just want to make sure that I have the correct information and others have the correct information. I see a ton of zc fireplaces especially the 42" models that are typically 20 plus years old that have new insets from a variety of manufacturers. And Im having trouble finding an example of zc fireplace manufacturer specifying specific model gas inserts that can be installed.

Screenshot_20211010-085154.png
 
Right.... But the manual does not say you can't install inserts into it. It says "Do not install a fireplace insert or other products not SPECIFIED for use with this fireplace". So who specifies? Some gas insert manufacturers specify. I just want to make sure that I have the correct information and others have the correct information. I see a ton of zc fireplaces especially the 42" models that are typically 20 plus years old that have new insets from a variety of manufacturers. And Im having trouble finding an example of zc fireplace manufacturer specifying specific model gas inserts that can be installed.

View attachment 283093
The fireplace manufacturer has to specify parts to work with their system. This is not my interpretation of it. It is the interpretation of every applicable professional training and certifying organization and ul is currently rewriting their listing criteria to clarify this issue.
 
The fireplace manufacturer has to specify parts to work with their system. This is not my interpretation of it. It is the interpretation of every applicable professional training and certifying organization and ul is currently rewriting their listing criteria to clarify this issue.
We definitely have two different interpretations of what is written. Why would majestic use that verbage if they do not then provide a list of their own of specified products? It makes no sense. For full disclosure I am not an installer, I am an independent service provider that does the maintenance and repairs for multiple fireplace shops. And I don't know of a shop, installer, or plumbing inspector in my entire county that has your interpretation of this. Could they all be wrong? Sure maybe. Although I don't do the installations I certainly want to be able to identify inserts that are not installed safely. At my next con Ed course I will certainly bring this up and seek clarification
 
We definitely have two different interpretations of what is written. Why would majestic use that verbage if they do not then provide a list of their own of specified products? It makes no sense. For full disclosure I am not an installer, I am an independent service provider that does the maintenance and repairs for multiple fireplace shops. And I don't know of a shop, installer, or plumbing inspector in my entire county that has your interpretation of this. Could they all be wrong? Sure maybe. Although I don't do the installations I certainly want to be able to identify inserts that are not installed safely. At my next con Ed course I will certainly bring this up and seek clarification
What training have you had? What did that training organization tell you about ul listed appliances and how their instructions relate to each other? I know for a fact many installers choose to do installs like this because it provides them with income. But by doing so they are completely disregarding the fireplace manufacturers instructions. And opening themselves up to massive liability.


And majestic does provide a list of specified products. They are all of the products listed in that manual. That's it.
 
Every convention and trade show I have been to has classes specifically on this and other issues involving prefab fireplaces. If it isn't specified in the fireplace manual or by a later official modification to that manual it is not an approved component and by code it can't be used.