Getting more heat from my Fisher Insert

[Flynnworx]

This is a truly awesome site! I have the same full size insert and want to get more heat out of it. I will check the chimney (exterior masonry) tomorrow; I know the clay flue extends out the top with a screened rain cover fitted over it. I can see a pipe or fitting going up into the chimney in the air space above stove and under wall cover/heat shield. I saw the thread about making a smoke shelf and will do that ASAP also.

 

[coaly]

Adding a blower if you don't have one is how to get the heat from convection out of the Insert.
You only get radiant heat from the front that protrudes from the fireplace along with the air that rises naturally out of the slot below heat shield. Convective heat is from the airspace between firebox and outer case around the back, sides and bottom of firebox. Looking into the slot above firebox is the vent pipe welded to the top of firebox that goes between the firebox and outer shell. You have to remove the upper front cover plate to see the chimney flue connection if there is one.

 

[Flynnworx]

My fireplace has 4 metal louvered covers with (rattling) fans in the 2 low ones. They need to be upgraded as well. The metal smoke shelf modification is brilliant.

 

[Flynnworx]

I bought this house a year ago and used the stove last year a few times, but was disappointed with the amount of wood it went through, so I figured I would replace it one day. Now I have hope in keeping it and getting her tuned up [emoji6]

 

[Flynnworx]

 

[coaly]

My fireplace has 4 metal louvered covers with (rattling) fans in the 2 low ones. They need to be upgraded as well. The metal smoke shelf modification is brilliant.

The louvers and fans are to remove heat stored in the masonry when burning as it was intended. An open fire radiates heat into the masonry which is stored and given up to the house interior. Radiation from the fire not only is directly into home, but reflects from angled sides or bounces back and forth between straight walls from the fire near the rear wall that heats the mass of the masonry. Unfortunately it also moves heat to the outside as well as upward to the outdoors. So internal passageways and blowers try to extract the heat by means of convection into the home.

The idea of installing an insert is to extract the heat directly from the firebox into the room with radiation from stove front and doors, plus through convection between the firebox and outer shell of Insert. Most Inserts are convection only being built flush with the hearth face requiring a blower to extract all the usable heat. Fisher is both radiant from the portion that sticks out and convection from the part inside the fireplace. There should be little to no waste going into the mass of masonry. The blowers you need either mount on the sides of the face plate when it has slots up and down the sides, or under the front that blows under the Insert, up the back, around the exhaust vent collar which is the hottest part to extract extreme heat from that area and out the top slot.
This thread shows the different blowers that were available as well as some homemade styles;
https://www.hearth.com/talk/threads/made-a-blower-for-my-fisher-insert.117672/

 

[coaly]

The reason for the direct connected flue liner is the same; Prevent heat from radiating into masonry flue by a smaller insulated pipe to keep the internal walls hot requiring less wasted heat up the chimney. The object is to keep flue gasses above 250* all the way up preventing condensing of water vapor in the flue allowing smoke particle to stick. This takes advantage of more BTU inside the home than wasted to keep the chimney clean and hot. The internal baffle will put more heat to the inside of home and decrease loss up the chimney, so an insulated liner is best to keep the flue hot enough as you make the insert more efficient.

 

[TattedActuary]

so if I'm wanting to get more heat from my Fisher insert, would you go internal baffle or blower first?

 

[Flynnworx]

Here's the shelf I installed; it definitely helped push more heat out right away. I am still playing around with blower options