Wood burning heat exchangers

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mjnicho1

New Member
Feb 23, 2024
22
R0y8a2n81987
Can you effectively stack two heat exchangers on the same flue pipe to double your heat output? I configured my wood burning stove this way but I'm having problems with the top heat exchanger staying on consistently.
[Hearth.com] Wood burning heat exchangers
 
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Can you effectively stack two heat exchangers on the same flue pipe to double your heat output? I configured my wood burning stove this way but I'm having problems with the top heat exchanger staying on consistently.View attachment 325103
Nope one is a bad idea 2 is a horrible idea
 
Nope one is a bad idea 2 is a horrible idea
I've been using the Magic Heat exchanger for the past 10 years and it works very consistently well by warming up about 2/3rds of my 1500 sq ft. house, raising the temperature by about 10 degrees within a little over an hour. I was hoping for the same effect in my back bedroom with the Miracle Heat exchanger.
 
The Magic Heat exchanger has served me well for the past 10 years heating up 2/3 rds of my 1500 sq. ft. house, raising the temperature about 10 degrees in one hour. I was hoping for the same in my back bedroom with the other Heat exchanger.
 
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You need to check your chimney for creosote. The heat exchangers cool the exhaust gas below the condensation Temperature
 
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Also the CO producing ash bucket nicely in the home...
 
You need to check your chimney for creosote. The heat exchangers cool the exhaust gas below the condensation Temperature
Yes, I have stiff nylon brushes I use to clean the single wall Duravent pipe each year before the cold weather sets in, and I burn hard wood only, I try to stay away from burning pine.
 
Yes, I have stiff nylon brushes I use to clean the single wall Duravent pipe each year before the cold weather sets in, and I burn hard wood only, I try to stay away from burning pine.
Nothing wrong with pine at all. What moisture content is your wood at? How much crap do you get in your chimney?
 
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Nothing wrong with pine at all. What moisture content is your wood at? How much crap do you get in your chimney?
Ditto the pine.

Pine is easy to process, lights very easily, and burns without clinkers. Oh - did I mention it is free?
As a consequence of living in a pine forest, I burn almost exclusively Ponderosa Pine and have close to zero creosote buildup. Dry wood does the trick.
 
Yes, I've got a 2 year old toddler. The kindling is in a stainless steel tub that is a little close to the stove. The radiant heat from the stove helps to dry out the kindling. The outside of the tub is barely warm to the touch even when the flue temperature is between 400 to 500 degrees.
 
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I let fresh cut wood dry for about a year before burning it. Our summers in the high desert of California can stay at 100+ degrees for weeks on end but the humidity is very low. I don't keep all of my firewood covered, so the moisture I'm concerned about is in the kindling when it rains.
 
A year at desert climate could be fine, depending on sun and wind exposure.

I don't like seeing flaky stuff as it means it was liquidlike when deposited. You want powdery stuff.
 
No joke, I had a similar setup with the same issue. My solution was to override the thermostat on the upper one... Can you say bad idea and chimney fire... Ignorance and arrogance on my part. Some of the longer tenured folks here may recall my "education period" when I was researching my new stove & flue install and proper burning technique.

I will only repeat what I have stated many times here. I wish I had installed the new stove and flue 15 years sooner. I safely use way less wood and get much more heat from the new setup. It's an upfront cost yes, but going from 5-7 cord to 3-4 with more effective heat is priceless...
 
It brushes off very easily when I run my brushes through the pipe.
What about your chimney? You are either running the stove wrong and dumping massive ammouts of heat out the chimney or you are going to have creosote issues