Idea for more heat from insert

[offroadaudio]

I'm talking about a Quad 4100I here.
Steel firebox, surrounded by a light-gauge steel convection jacket. The blower pulls air in from the bottom front of the stove - it goes up the back - and out over the top to the front.

Now. All of this air is moving between the firebox and convection jacket which are SMOOTH.
I'm thinking about adding some "fins" to the inside of the convection jacket to create a sort of maze for the air flow. This would slow the air down and therefore heat it up more. Just like any heat exchanger - surface area is key.

Cons?
Lots of meticulous work
might be noisy - pings and tings

Why don't manufacture's do this? (maybe because it won't work?) - maybe just a cost thing?

 

[Shari]

It sounds like you are saying 'low speed' on your fan is too 'high'. Just plug your fan into a rheostat = infinite speed control on your fan.

EDIT: Here's an example - http://www.amazon.com/Dial-A-Temp-Rheostat/dp/B002JLEZS6/ref=sr_1_7?ie=UTF8&qid=1295965896&sr=8-7

 

[offroadaudio]

It sounds like you are saying 'low speed' on your fan is too 'high'. Just plug your fan into a rheostat = infinite speed control on your fan.

EDIT: Here's an example - http://www.amazon.com/Dial-A-Temp-Rheostat/dp/B002JLEZS6/ref=sr_1_7?ie=UTF8&qid=1295965896&sr=8-7

This blower does have the rheostat control.
This idea would theoretically transfer more heat to the passing air, no matter the fan speed.

 

[begreen]

They do this on some pellet stoves in the convection heat exchanger.

 

[offroadaudio]

Ok, so it might be a worthwhile thought.
I'll have to brainstorm on how to do it easily, and be able to "go back" if it doesn't work out.

 

[begreen]

Does the 4100i convect very well naturally, without the blower running?

 

[offroadaudio]

I would say no.
It really needs the blower.

 

[Jags]

Take some very thin sheet metal (a sheet that matches the size of the surround panel) and punch "tabs" into it (-- -- ). You can attach this inside of the surround. If it works, make it permanent, if not - remove it. My guess is that you will notice very little temp difference if matching volume to volume (air entering the room).

 

[CountryBoy19]

I'll weigh in on this a little.

What is your ultimate goal? To get the most heat out of the insert or get the highest air temp coming from the blower? Those 2 options are very different, and require the exact opposite actions.

If you want to get a higher air temp, then slowing the air down and "channeling" it to run across more surface area of the stove will do that. But it will decrease the actual BTU's that you're getting out of the stove.

If you want to get the most BTUs out of the insert you want to blow air as cold as possible over the surface as fast as possible. To do this I would leave it be; your only real option is increase air speed/volume. Adding fins won't help you very much. Thin fins on thin plates don't help nearly as much as thicker fins on thick plates. I would say you won't see any noticeable difference in the BTU output or air temperature doing this. If you still want to do fins you would need to weld the fins on to get the best heat transfer to the fins.

I'm thinking about adding some "fins" to the inside of the convection jacket to create a sort of maze for the air flow. This would slow the air down and therefore heat it up more. Just like any heat exchanger - surface area is key.

Adding fins to the convection jacket won't increase heat transfer because you're not trying to transfer the heat from the convection jacket, you're trying to transfer it from the stove. Fins added to the jacket would only act to channel the airflow.

There is a lot more science to fin design than you may think.

 

[FGZ]

I've wondered the same thing. Thicker aluminum fins (like on an air-cooled small motor) along the top of the firebox, under the convection jacket. Seems like it would exchange more heat.

 

[tynman]

Seems to me like you'd get more radiant heat with the fins, but colder air coming out of the blower since some of that heat is being directed to the fins.

 

[CodyWayne718]

There was a thread about how ppl run their blowers on their inserts awhile back, I posted that I let mine get up in temp before I turned the blower on after reloads. However I have discovered that leaving the blower on high even right after reloads. Guess I'm jus curious as to how you run yours....

 

[offroadaudio]

On high all the time - except when loading

 

[GeoJoe]

Regency recommends turning off the blower on the I1200 insert for 20min after a reload. This seems way too long for me to wait for hot air. So I'll give it a few minutes to get cooking again to turn it on. If I turn it on high right after reload and I don't have a big enough coal bed, I run the chance of smother and smolder.

You've probably already considered running just the fan on your home's AC/heat unit. This will bring colder air from other rooms and push warmer air throughout the house.

 

[offroadaudio]

Regency recommends turning off the blower on the I1200 insert for 20min after a reload. This seems way too long for me to wait for hot air. So I'll give it a few minutes to get cooking again to turn it on. If I turn it on high right after reload and I don't have a big enough coal bed, I run the chance of smother and smolder.

You've probably already considered running just the fan on your home's AC/heat unit. This will bring colder air from other rooms and push warmer air throughout the house.

My experience has been that introducing all of that duct loss and velocity has a cooling effect, but each house is different.

 

[Huskyforlife]

In my opinion, three things to get the most heat out of an insert. Add block off plate if not installed already. Stuff rock wool insulation all around the stove in the fireplace. And crank the blower on high.