Some questions about primary, secondary and airwash controls...

[pault123]

Evening guys,

Here's some points in the manual for my Stockon 5.

It talks a lot about not keeping the stove in boost setting on the airwash, and closing the primary down once the fire is going.

I've been leaving it in boost and also the primary open until its upto 350 *F. Then closing air down to slowly rise up to 400-450* F. Are all these warnings simply for people without a stove thermo to prevent overfiring? ie. as long as temps are in check no harm can be done from keeping the air controls open fully to get things going?

Secondary air - i've not really figured out, and left at 50%, doesn't appear to have much impact burning wood from what i've seen so far?

It also talks about burning a new load for a few minutes with primary open before adjusting it closed again, but i've found it better with primary open for 10-15 minutes to get a new load going properly?

Hottest i've had it so far is 500 on the flue thermo, I was concerned at this as its in the "too hot" area on the thermo and shut things down to bring it back to 450. Should I be concerned at 500 temps?


Just a sanity check really to make sure i'm running it ok and not causing damage

 

[Woody Stover]

That looks like it's got a lot of control over the air inputs. You have a magnetic surface thermo on the flue, on single-wall connector pipe? How far above the stove top is it? I think as long as you don't go over 500, you should be OK. Do you have a stove top thermometer as well? That will help you determine that the stove isn't over-firing when you have it set for the long haul. When bringing a stove up to temp, I generally want medium flame in the box, not a roaring fire that may overheat the pipe. It looks like the secondary air control will govern how well the stove re-burns the smoke at different stages of the burn, so you'll probably have to experiment with that to see what works best when starting a fresh load, and when setting the stove for a long burn. They mentioned not having big flames that come up to the glass so I'm guessing that smaller, bluer flames might indicate a cleaner burn? Maybe you can tweak it to get cleaner burns at different stages. As you said, I'd think the secondary air would have minimal effect on how the wood itself is burning. Sounds like you may use a little primary air at the end of the burn to reduce the size of the coal bed while still getting some heat out of the stove. I burn cat stoves so I'm guessing at what the air controls may do on your type of stove.
"Refuel little and often for clean, efficient burning." Interesting, this is the opposite of how many on here burn their stoves...the "batch burn," i.e. load it up and then burn it down until there's only enough coals to ignite a fresh load.

 

[begreen]

Nice stove. It has the additional controls for multifuel burning.

If the flue is just briefly touching 500F on startup or after a reload catches fire that is ok, but it should not stay at that temperature for a long time. The actual flue gas temperature inside the pipe is about 75% higher than the surface reading. Ideally, once the stove is up to temperature you want the flue temp to be reading about 100F less than the stove top temperature.

For wood burning, after switching the boost air to optimum try reducing the primary air until the flame start getting lazy and open up the secondary air a bit more, say to 75%. Let the fire regain strength on its own, then turn down the air again until the flames get lazy. Once the fire is totally in the coaling stage and the flames have died down you push in the secondary control to close it. That will help extend the burn.

 

[pault123]

That looks like it's got a lot of control over the air inputs. You have a magnetic surface thermo on the flue, on single-wall connector pipe? How far above the stove top is it? I think as long as you don't go over 500, you should be OK. Do you have a stove top thermometer as well? That will help you determine that the stove isn't over-firing when you have it set for the long haul. When bringing a stove up to temp, I generally want medium flame in the box, not a roaring fire that may overheat the pipe. It looks like the secondary air control will govern how well the stove re-burns the smoke at different stages of the burn, so you'll probably have to experiment with that to see what works best when starting a fresh load, and when setting the stove for a long burn. They mentioned not having big flames that come up to the glass so I'm guessing that smaller, bluer flames might indicate a cleaner burn? Maybe you can tweak it to get cleaner burns at different stages. As you said, I'd think the secondary air would have minimal effect on how the wood itself is burning. Sounds like you may use a little primary air at the end of the burn to reduce the size of the coal bed while still getting some heat out of the stove. I burn cat stoves so I'm guessing at what the air controls may do on your type of stove.
"Refuel little and often for clean, efficient burning." Interesting, this is the opposite of how many on here burn their stoves...the "batch burn," i.e. load it up and then burn it down until there's only enough coals to ignite a fresh load.

Evening Woody Stover,

I have a Stovax thermo around 18" inches up on the stove pipe, I think its single wall.

I've never thought of having another one on top of the stove, but as there only £10, i'll pick one up. Where abouts on the top would I put it based on above pic?

I've not really had any blue flames so far, only blue I can see is a slight hue close to the base of the flame.

With batch burning would you typically rake the embers forward before a reload then stack the wood east west in a stove of this orienation? I've been putting wood on so far before it gets to complete embers stage trying to keep the temps always between 350-450 *F.

 

[pault123]

Nice stove. It has the additional controls for multifuel burning.

If the flue is just briefly touching 500F on startup or after a reload catches fire that is ok, but it should not stay at that temperature for a long time. The actual flue gas temperature inside the pipe is about 75% higher than the surface reading. Ideally, once the stove is up to temperature you want the flue temp to be reading about 100F less than the stove top temperature.

For wood burning, after switching the boost air to optimum try reducing the primary air until the flame start getting lazy and open up the secondary air a bit more, say to 75%. Let the fire regain strength on its own, then turn down the air again until the flames get lazy. Once the fire is totally in the coaling stage and the flames have died down you push in the secondary control to close it. That will help extend the burn.

Thanks for the advice, i've not really tried shutting the airwash down to get lazy flames yet, I thought less air would = dropping temps + creosote. So its been burning with a slight roar noise with air wash at exactly 50%. I'll try closing it more tomorrow and see how it goes

 

[begreen]

Once the stove is warming up move the airwash control to the middle position. Then, reduce the Primary air control to make the flames lazy.

 

[Woody Stover]

Once the stove is warming up move the airwash control to the middle position. Then, reduce the Primary air control to make the flames lazy.

Manual seems to indicate that with wood, you burn with the primary closed, and the air wash and secondary are supplying the air.
http://www.stovax.com/download/Tech...Stockton Installation & User Instructions.pdf

 

[begreen]

That's correct, though they get a bit more specific. Everything is wide open for fire starting. The primary air is the main regulator once the fire is going well. The air wash and secondary air remain partially opened. I would experiment with closing down the secondary air once the fire is in the coaling stage to further extend the burn time.

 

[Woody Stover]

Where abouts on the top would I put it based on above pic? With batch burning would you typically rake the embers forward before a reload then stack the wood east west in a stove of this orienation? I've been putting wood on so far before it gets to complete embers stage trying to keep the temps always between 350-450 *F.

If the top of the stove is the top of the fire box, try to find the hottest spot for the thermo. But it's possible to run the stove as you have been, with the flue meter, and keeping it 350-450F sounds like the stove would be well under control. Are those the temps recommended in the manual? Didn't see any temp references when I perused it. Batch burning, you could load wood either way but E-W would probably give you a longer, more controlled burn. The log guard attachment might keep wood from falling against the glass when loading E-W. Letting the load burn down farther would also give you a bigger temp swing, flue might drop well under 350. Maybe with a full load at night, you'll have enough coals left to re-load on the fly when you wake up? But the manual seems to recommend adding a few pieces at a time, so I don't know which way might be cleaner or more efficient overall. I guess they could be trying to prevent over-firing by suggesting that you only add a couple of pieces at a time...