Replacing natural gas fireplace with pellet stove.

[vivaunix]

Hello!
I have s gas fireplace that I do not use. It is just a decor item that works but does not produce heat.
I would like to replace it with pellet stove.
Please, help me to understand what I need:
- can i reuse the chimney? It looks like a 6", can I use some sort of adapter 3-to-6 for it?
- what do I need to know/see after removing my fireplace out?

The hole is like 63" wide and 50" toll from wood trims. I want to remove everything and put the firestove in, not insert, the standing pellet stove. I am looking into ComfortBilt HP22.

Thank you!

Chimney output:

Fireplace:

I plugged in the whole with insulation:

 

[johneh]

I pulled my fireplace out (zero clearance wood burner
reused the class A chimney with a 3 to 6 adapter
and reworked the opening. has a stand-alone Envrio
been using it for 22 years

 

[vivaunix]

Do you have a cold air intake from the back?
How do I know what class chimney I have?

 

[johneh]

Yes I have an OAK installed
I have no idea what chimney you have but
because it is gas it has to be fire safe double lined and
installed in a workman-like manner. This most likely
makes it pellet stove-safe but that is for you to decide