Rsf Opel 2 secondary air modification

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Hey ABMax24 thanks for all the info very helpful! So i have the same fireplace as Crocks and im currently building a similar setup to his. Our Air wash comes down above the glass and my question is do you think by drilling the 1/8'' holes in the bigger Tube pointing toward the glass would effect the way the air wash works in a negative way? Thank you!

It's possible but I don't think it would, particularly if orfices are installed to limit the velocity out of the holes.
 
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I guess, I run a pressure piping shop, the thought of tack welding holes shut in tubing makes me cringe.

Not to mention if you are using 300 series stainless you'll probably end up with a banana once you're done closing the extra holes, and if you're using 400 series drilling new holes isn't much different than drilling normal carbon steel.
 
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Here’s the inside of my catalytic unit for reference. I still have a secondary burn tube but it doesn’t go very often. Doesn’t look as though they change much for catalyst, just direct the heat towards the catalyst in the front. It looks like I could modify my burn tube system to be more like what you have done and have a hybrid. I’d honestly prefer the burn tubes, I’m on my second cat.
 

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Those coals are what was left this evening at almost 6 after I reloaded at 4:15 this morning. The burn tube is not visible, it’s under the v shaped plate just below the cat.
 
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Here’s the inside of my catalytic unit for reference. I still have a secondary burn tube but it doesn’t go very often. Doesn’t look as though they change much for catalyst, just direct the heat towards the catalyst in the front. It looks like I could modify my burn tube system to be more like what you have done and have a hybrid. I’d honestly prefer the burn tubes, I’m on my second cat.


Where is the control for the bypass located ? How long did the first cat last?
 
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@Crocks if you look in the first picture the air control for the unit is in the bottom right corner. The first cat lasted three seasons and then I started to get major smoke roll into the house. Found out that it was completely blocked by ash on the back side. So I went ahead and replaced it. It might still be good yet, I plan to try it but have been running the new one.
 
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Check this out. I loaded 4 splits last night at 830. 1 small, 2 medium all oak. And one bigger peice of madrone . Nothing over 6" dia. I closed the stove down a little earlier than typical and this is what I get. Not even a few minutes after this video the secondarys picked up and put off more orange flames.

This morning at 630 am . I had a ton of coals. Put 3 big splits on . Fired right up. Within 15 mins I had it shut down and off to work I go...
Feast your eyes!!!

 
Check this out. I loaded 4 splits last night at 830. 1 small, 2 medium all oak. And one bigger peice of madrone . Nothing over 6" dia. I closed the stove down a little earlier than typical and this is what I get. Not even a few minutes after this video the secondarys picked up and put off more orange flames.

This morning at 630 am . I had a ton of coals. Put 3 big splits on . Fired right up. Within 15 mins I had it shut down and off to work I go...
Feast your eyes!!!


That's awesome! Nice work. Now you got me second guessing on drilling the holes in the front Burner LOL
 
Check this out. I loaded 4 splits last night at 830. 1 small, 2 medium all oak. And one bigger peice of madrone . Nothing over 6" dia. I closed the stove down a little earlier than typical and this is what I get. Not even a few minutes after this video the secondarys picked up and put off more orange flames.

This morning at 630 am . I had a ton of coals. Put 3 big splits on . Fired right up. Within 15 mins I had it shut down and off to work I go...
Feast your eyes!!!


That's more like it. I have repeated hundreds of times to folks to try closing down the air earlier to extend the burn. As long as the wood is dry and draft is good, this can make a very big difference.
 
I see so just one control total? Do you have a strandard air control aswell like the Opel 2? Maybe they are connected together

I just have one air control lever just the same as a pre catalytic Opel. Only difference is that I have a bypass rod to open or close the bypass for the cat. It also has the same bimetallic damper but per the manual I always adjust the air manually. Mine being catalytic I had to have an outside air kit as well (manufacturers requirement). Looks like you’re really getting a good burn with your modifications.
 
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Man, that's better than my stove will do. Looks like you may be a little shy on primary air.
It's hard to see but in the video under the front log there is a mini inferno going. I honestly think I have it about right. When the fire is about around the peak, I feel I could cut the primary air more.
 
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I just have one air control lever just the same as a pre catalytic Opel. Only difference is that I have a bypass rod to open or close the bypass for the cat. It also has the same bimetallic damper but per the manual I always adjust the air manually. Mine being catalytic I had to have an outside air kit as well (manufacturers requirement). Looks like you’re really getting a good burn with your modifications.
Thank you . I would still like to add the cat option just to see. For me it's not about saving a ton of wood that drives me. (I have 10 years full in my yard) what does is the fact the fire burns really hot then holds a coal for a lot longer . This is almost magic to me maybe just something awsome called secondary combustion

Hey if you ever have that top louver out, shoot us a pic of the bypass linkage. If it even tells much
 
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Here is the exploded view which for visual purposes is the best at explaining the catalyst and bypass system. The bypass itself is a pretty simple system, just slides there on top of the baffle in top of the firebox. I presume there would have to be for your application a completely new upper baffle with room for the catalyst to mount to. Based on where you are at with your burn, sounds like you are already getting better burn times that I am with your modifications. I need to start learning now how you've controlled your primary air. I feel that with 28 ft. of chimney my draft may be a little strong. I haven't tried closing down some of my air inlet to see if that helps.
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Here is the exploded view which for visual purposes is the best at explaining the catalyst and bypass system. The bypass itself is a pretty simple system, just slides there on top of the baffle in top of the firebox. I presume there would have to be for your application a completely new upper baffle with room for the catalyst to mount to. Based on where you are at with your burn, sounds like you are already getting better burn times that I am with your modifications. I need to start learning now how you've controlled your primary air. I feel that with 28 ft. of chimney my draft may be a little strong. I haven't tried closing down some of my air inlet to see if that helps.
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Is this called an Opel 3 catalyst kit? Maybe they are all the same
 
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That’s a high probability that they are the same. If stove manufacturers know anything about common parts I would imagine the kits is the same stuff I am using.
 
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Last night I started a top down fire at 630 pm. (Full load)

This is my coal bed exactly12n1/2 hrs later . I Tossed in 3 oak splits. Within 10 mins I had the stove closed down at 300, and she climed to 350 instantly
 

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