Well I got my Solo 40 hooked in parrell to my oil boiler. I have never seen the flue temp. get over 400 F., now I am. I have tried to adjust the secondary air to max and min and that does not seem to effect it. I have a clean chiminey and get about .005 WC when it is firing. The fan on the boiler is adjusted to full open when running and closes when off. I am burning fire killed spruce. When I look in the viewing window it is not a real roaring/glowing fire that I would expect and adjusting the secondary air does nothing to the flame pattern. I am a loss here. Can someone give me some direction please? Thansk Doug
solo 40 temp. trouble
- Thread starter dougcarlo
- Start date
-
Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.
We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.
We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
- Status
steam man
Minister of Fire
Typically when I see stack temps rise it means the boiler's heat exchanger is not absorbing heat. Check your boiler tubes for build up of cresote/carbon. Sounds like the Tarm needs a cleaning.
Mike
Mike
sweetheat
Member
try adding dry hardwood, check the flue diameter, it maybe to large, they require a 6" flue. sweetheat
jebatty
Minister of Fire
Some of your problems were the same ones I had last fall when I first hooked up my Tarm Solo 40. Hope this helps.
Wood: I burn mostly dry pine slabs, and these are dry. The resin in pine tends to cause it to burn hotter than some other woods. Also the dryness leads to the same result. Mine is dried at least 2 summers. I have not changed my wood, but I have changed how I burn it, and the results have been satisfactory.
Flue temp: A higher flue temp relates in part to burning dry wood, especially pine, and I suspect spruce too. I got hung up on those who advocate a 300-400 flue probe temp. Not that they are wrong; only that there are so many variables involved in this, including dryness of wood, chimney conditions, height, winds, obstructions in the area, secondary air setting, and probably a lot more. For me the long and short is that I almost always can "light it and forget it" with the secondary air control set at about the midpoint for an efficient, sustained, smokeless burn if I just let the boiler burn wood and let the flue temp vary between about 350-600, with the bulk of the burn in the 400-500 range. I'm not hung up on absolute, maximum efficiency; I am hung up on achieving a "light it and forget it" burn.
Draft fan: It took me quite a time to adjust the draft fan damper down enough, as I was getting flue temps up to almost 1000, and that is too hot. Be sure to actually adjust the knob that controls the damper opening. I thought I had the damper adjusted down all the way and then discovered that the adjusting knob could be further adjusted. I mostly achieved a satisfactory flue temp after some more draft fan damper adjustment, and I closed it down a lot. I also added and tried a motor speed control for the draft fan. It fit nicely on the control panel. I'm not advocating this, but it is an option which can help control draft. I think my real problem was that my chimney produces an excellent draft, and the chimney draft was sucking lots of air through the draft fan damper opening, in effect giving a real boost to the draft fan.
Turbulators: This was the coup d'etat in me achieving the most satisfactory final result. Take a look at this link to see what I'm talking about. When I added these, my flue temp dropped somewhat more than 100 degrees. I clean these every 2 weeks to one month, and I know they need cleaning when flue temp starts to rise again higher than when they are clean. Commercial turbulators are available, including some from Tarm, but mine were free, easy to make, easy to install, and should last forever due to the heavy duty chain I had.
https://www.hearth.com/econtent/index.php/forums/viewthread/17662/P15/#192106
Secondary air adjustment: This adjustment controls the relative amount of primary air to the firebox and heated air to the gasification chamber. During my early experience, it seemed to me also true that adjusting this had no effect. I focused on the manual statement to set it in the middle and forget it, as I am not about to sit by the boiler and frequently adjust this air control. Again, there are so many variables involved that in the ideal situation, secondary air probably should be continuously adjusted to achieve maximum burn. Not for me. Less dry wood does require a little more air in the firebox (move the control towards -) and drier wood requires a little less air in the firebox (move the control towards +). Best, set it in the middle and forget it, or at another point which approximates efficient burn for the mositure content of your wood.
Achieving a satisfactory burn ("light it and forget it"): the key to this is quickly getting a hot bed of coals at the bottom of the firebox and on top of the gasification slot. Gasification works when the hot gases from the firebox are driven down through the hot bed of coals and then into the gasification tunnel. If you don't have that hot bed of coals, or if the slot opening is blocked by wood or by chance too many coals, you won't get a good gasifying burn.
1) get a hot fire, with hot coals at the bottom, burning fast. Start with small kindling, 3-4 layers loosely criss-crossed, bypass damper open, both door ajar, draft fan on. I use the top down fire starting method, as this tends to minimize any fire starting technique that blocks the gasification slot. When this is burning really well, add small splits to fill the firebox about 1/4 full, and let this get burning really well. Then close the two doors, shut the bypass damper, and you should almost immediately get a strong blasting flame into the gasification tunnel. Let this burn for a few minutes to heat the tunnel. Total time for all of this should be no more than 5-15 minutes.
2) Now fill the firebox. I put smaller splits in first, and then larger and heavier ones at the top, going from smaller to larger until the firebox is full, but not packed. I do a little slight angular loading of some pieces to minimize the wood load hanging up during the burn process. The reason for this order is that occasionally "bridging" can occur. Search this term to find out what this is all about. By putting smaller at the bottom and heavier at the top, the heavy splits have the weight to continue to collapse the burning splits below and minimize the likelihood of bridging. Bridging results in interruption in good gasification and smoke out the chimney. Bridges will correct themselves and collapse on their own, but the technique described I have found minimizes the formation of bridges.
3) Other burn issues: keep your splits small, 4-6" range. The Tarm is made in Denmark, and I think normal wood there is round wood in the 4-6" range (maybe I'm wrong). Round wood inherently slips and slides as it burns. Splits, with their angular faces, tend to pack and hang up. Small splits do this less than big splits. If all you have are large splits, in the future split smaller, and you might consider resplitting some of the larger splits, or if you can, use those for on top of the wood load. Also, although the manual says 20" splits, I cut 18". The little extra space tends to minimize the wood load hanging up in the firebox and cause bridges.
4) A little frustrating for me at the start, now great and easy satisfaction. Perfection is an unreasonable goal -- but I think I've gotten pretty close to that.
5) Good luck!
Wood: I burn mostly dry pine slabs, and these are dry. The resin in pine tends to cause it to burn hotter than some other woods. Also the dryness leads to the same result. Mine is dried at least 2 summers. I have not changed my wood, but I have changed how I burn it, and the results have been satisfactory.
Flue temp: A higher flue temp relates in part to burning dry wood, especially pine, and I suspect spruce too. I got hung up on those who advocate a 300-400 flue probe temp. Not that they are wrong; only that there are so many variables involved in this, including dryness of wood, chimney conditions, height, winds, obstructions in the area, secondary air setting, and probably a lot more. For me the long and short is that I almost always can "light it and forget it" with the secondary air control set at about the midpoint for an efficient, sustained, smokeless burn if I just let the boiler burn wood and let the flue temp vary between about 350-600, with the bulk of the burn in the 400-500 range. I'm not hung up on absolute, maximum efficiency; I am hung up on achieving a "light it and forget it" burn.
Draft fan: It took me quite a time to adjust the draft fan damper down enough, as I was getting flue temps up to almost 1000, and that is too hot. Be sure to actually adjust the knob that controls the damper opening. I thought I had the damper adjusted down all the way and then discovered that the adjusting knob could be further adjusted. I mostly achieved a satisfactory flue temp after some more draft fan damper adjustment, and I closed it down a lot. I also added and tried a motor speed control for the draft fan. It fit nicely on the control panel. I'm not advocating this, but it is an option which can help control draft. I think my real problem was that my chimney produces an excellent draft, and the chimney draft was sucking lots of air through the draft fan damper opening, in effect giving a real boost to the draft fan.
Turbulators: This was the coup d'etat in me achieving the most satisfactory final result. Take a look at this link to see what I'm talking about. When I added these, my flue temp dropped somewhat more than 100 degrees. I clean these every 2 weeks to one month, and I know they need cleaning when flue temp starts to rise again higher than when they are clean. Commercial turbulators are available, including some from Tarm, but mine were free, easy to make, easy to install, and should last forever due to the heavy duty chain I had.
https://www.hearth.com/econtent/index.php/forums/viewthread/17662/P15/#192106
Secondary air adjustment: This adjustment controls the relative amount of primary air to the firebox and heated air to the gasification chamber. During my early experience, it seemed to me also true that adjusting this had no effect. I focused on the manual statement to set it in the middle and forget it, as I am not about to sit by the boiler and frequently adjust this air control. Again, there are so many variables involved that in the ideal situation, secondary air probably should be continuously adjusted to achieve maximum burn. Not for me. Less dry wood does require a little more air in the firebox (move the control towards -) and drier wood requires a little less air in the firebox (move the control towards +). Best, set it in the middle and forget it, or at another point which approximates efficient burn for the mositure content of your wood.
Achieving a satisfactory burn ("light it and forget it"): the key to this is quickly getting a hot bed of coals at the bottom of the firebox and on top of the gasification slot. Gasification works when the hot gases from the firebox are driven down through the hot bed of coals and then into the gasification tunnel. If you don't have that hot bed of coals, or if the slot opening is blocked by wood or by chance too many coals, you won't get a good gasifying burn.
1) get a hot fire, with hot coals at the bottom, burning fast. Start with small kindling, 3-4 layers loosely criss-crossed, bypass damper open, both door ajar, draft fan on. I use the top down fire starting method, as this tends to minimize any fire starting technique that blocks the gasification slot. When this is burning really well, add small splits to fill the firebox about 1/4 full, and let this get burning really well. Then close the two doors, shut the bypass damper, and you should almost immediately get a strong blasting flame into the gasification tunnel. Let this burn for a few minutes to heat the tunnel. Total time for all of this should be no more than 5-15 minutes.
2) Now fill the firebox. I put smaller splits in first, and then larger and heavier ones at the top, going from smaller to larger until the firebox is full, but not packed. I do a little slight angular loading of some pieces to minimize the wood load hanging up during the burn process. The reason for this order is that occasionally "bridging" can occur. Search this term to find out what this is all about. By putting smaller at the bottom and heavier at the top, the heavy splits have the weight to continue to collapse the burning splits below and minimize the likelihood of bridging. Bridging results in interruption in good gasification and smoke out the chimney. Bridges will correct themselves and collapse on their own, but the technique described I have found minimizes the formation of bridges.
3) Other burn issues: keep your splits small, 4-6" range. The Tarm is made in Denmark, and I think normal wood there is round wood in the 4-6" range (maybe I'm wrong). Round wood inherently slips and slides as it burns. Splits, with their angular faces, tend to pack and hang up. Small splits do this less than big splits. If all you have are large splits, in the future split smaller, and you might consider resplitting some of the larger splits, or if you can, use those for on top of the wood load. Also, although the manual says 20" splits, I cut 18". The little extra space tends to minimize the wood load hanging up in the firebox and cause bridges.
4) A little frustrating for me at the start, now great and easy satisfaction. Perfection is an unreasonable goal -- but I think I've gotten pretty close to that.
5) Good luck!
Thanks for you r comments. One thing I am not doing is filling the boiler full, maybe 1/2. I will try it full. Doug
Well I started from scrath, cleaned boiler tubes, chiminey, and started fire with smaller diameter wood. I think the big wood was my main problem. I am so used to filling my old Kerr boiler with the biggest and longest pieces of wood and waiting a couple of hours to fill it again. Flue temp. was around 580 F. So thanks again for your help.
- Status
Similar threads
