Replacement of older insert

[nuska]

I came across a good deal on a HI300 at auction. I have an old suburban FP8-84U(I've never been able to figure out what those numbers mean). Its pretty but heat output I found lacking. it would heat the room its in (400sqft)but thats about it. After pulling it out it just has a rectangle shaped hole and vents directly into the chimney. So I would like to discuss what I can do to make sure this one is a success! The fireplace looks to have a steel frame that had the damper attached but its gone now. The frame does make it a offset up into the chimney through a seven inch gap. Based on what I've seen on here do you think a 6 inch SS flex kit with the 1/2 inch insulation be the safe bet?

I have a tangent question regarding a part that was missing. There is an insulation kit that comes with the faceplate that was missing. The insulation is used to make the seal against the face of the fireplace. On my old FP8 they had a caulk of some sort that had degraded so I stuff strips of standard fiberglass insulation in there and it did great. Do you think that would be a good idea here or is there a better way

 

[bholler]

I came across a good deal on a HI300 at auction. I have an old suburban FP8-84U(I've never been able to figure out what those numbers mean). Its pretty but heat output I found lacking. it would heat the room its in (400sqft)but thats about it. After pulling it out it just has a rectangle shaped hole and vents directly into the chimney. So I would like to discuss what I can do to make sure this one is a success! The fireplace looks to have a steel frame that had the damper attached but its gone now. The frame does make it a offset up into the chimney through a seven inch gap. Based on what I've seen on here do you think a 6 inch SS flex kit with the 1/2 inch insulation be the safe bet?

I have a tangent question regarding a part that was missing. There is an insulation kit that comes with the faceplate that was missing. The insulation is used to make the seal against the face of the fireplace. On my old FP8 they had a caulk of some sort that had degraded so I stuff strips of standard fiberglass insulation in there and it did great. Do you think that would be a good idea here or is there a better way

You will need to cut out some of the back of the fireplace to make it fit. And do lots of cleaning. What size is the existing flue?

 

[nuska]

You will need to cut out some of the back of the fireplace to make it fit. And do lots of cleaning. What size is the existing flue?

I have a sweep coming on Friday. its a 10 inch flue. So 6" + 1/2" insulation won't fit through that 7 inch gap between the steel box and the flue. Could I just not insulate the last 3 feet of liner?

 

[bholler]

I have a sweep coming on Friday. its a 10 inch flue. So 6" + 1/2" insulation won't fit through that 7 inch gap between the steel box and the flue. Could I just not insulate the last 3 feet of liner?

You will never make the nessecary bends to get the insert hooked up without cutting it.

 

[nuska]

You will never make the nessecary bends to get the insert hooked up without cutting it.

You think I can just use some rockwool for this insulation to seal against fireplace face?

 

[begreen]

That old insert looks new. It has a resemblance to the old Squire inserts.

 

[bholler]

You think I can just use some rockwool for this insulation to seal against fireplace face?

No need to seal around the face at all. Make a plate to seal around the liner as it passes through the old damper.

 

[nuska]

That old insert looks new. It has a resemblance to the old Squire inserts.

in hindsight, maybe I should have worked with what I had. I'm not sure if running a pipe up the chimney and installing a blocker plate would have fixed my problem or not. My in-laws have a stove that will almost run you out of their 2000 sqft single level. With ours, around the holidays people would all gather right in front of the fireplace just to get toasty. I got the hi300 for 1400 and looks like I can get a 300 tax credit. If I can sale the old one for a little and this one heats well then I think I'll be satisfied.

 

[nuska]

No need to seal around the face at all. Make a plate to seal around the liner as it passes through the old damper.

I do plan on building that. I've seen some how-tos on here. Just want to reiterate what i think the process will be as there has been some variations in design.

1. make a cardboard template 3-4 inches above liner connection to stove
2. transfer template to sheetmetal and add 1inch for the edges
3. bend edges down and cut out hole for pipe
4. place rockwool on top of sheetmetal, run liner through hole, stuff rockwool around liner to fill gaps and attach to stove
5. attach block plate to the existing steel fireplace frame
6. seal around edges with silicone

 

[begreen]

The most important factor in creating good heat with the new insert will be dry, fully seasoned wood. Even the best of stoves will heat poorly if the wood is not well seasoned.

 

[nuska]

We finished the install today. You were right @bholler we could not make the turn into the top of the insert because of the damper slot so we had to cut that out. I did not insulate the whole liner but did put a block plate topped with rockwool. Then, when i installed the roof cap I stuffed rockwool around the liner before putting the top on effectively sealing off the two ends of the liner. Now that I'm sitting here thinking about it though should I make that seal airtight? I noticed when shining a light through the top of the stove I got some light out where the bands tighten up around the liner from the appliance connector which would probably let a little smoke out and once its out of the liner there is no place for it to go.

 

[BigJ273]

I think the draft will pull it right past those smalls cracks, like a vacuum. Or so I’ve been told. I’ve often wondered the same thing. I had some small spaces light would shine through Around the connections as well. I can’t imagine you would ever have a completely air tight seal around the connections. The theory is that the draft pulls the smoke upward. I hit it with some furnace cement for piece of mind. It lasts about a season before I have to hit it with some more because it just gets brittle and falls off.