Can anyone tell me where the air actually enters the firebox on this fireplace? I'm using this unit for the second season now. Liking it a lot, but noticed the last couple of fires I've run don't seem to burning near as hot. I'm having to keep the air control open more than normal to get a good burn. And even doing that I'm smoking the glass more than usual. Same wood as I've been burning so far this season without this issue. No outside air kit installed. I just swept the flue a month ago before using the fireplace this year, I can't imagine it's restricted at all, but I'll go up on the roof and pull the cap to verify. I know there is a small boost air hole in the center of the andiron but I don't know where the main air comes in at. I just want to verify it's not being restricted in some way. Thanks for any info.
Osburn Strattford II air intake question
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The problem most likely is with draft being weaker or this batch of wood is not fully seasoned. Weak draft can be the result of a clogged chimney or cap.
I took like my Stratford 2, but it is a bit finicky.
Outside air temperature affects draft a lot too. Even with the easy breathing NC30 at home the difference between 40 and 30 is noticable.
I was told by an SBI tech that the air comes in the right side intake to a control box that the slide regulates. There are supposedly 2 holes in this control box. One the slide covers/uncovers to regulate air to the andiron, the other hole is not regulated and supplies air to the air wash and secondary tubes. This box can be accessed by removing the screws that hold the slide assembly plate on the front of the fireplace. I never pulled mine off to look at it.
I have an outside air kit on my Stratford 2 up in the Northwoods and it is not an easy breather with it. The fireplace and flue have to be HOT for it to draft well even with 19' of straight up flue, and that's a lot of steel to heat up. It takes forever for the rheostat to kick the blower on automatically so I usually turn it on manually when it starts to give some heat then switch it to auto once it will stay on there. It stays on for a long time on auto even after the fire has died down, but if it kicks off again it takes forever again to kick back on automatically. There must be a big temperature difference in the on/off settings of the rheostat.
I was given advice on getting it going by an original Stratford owner that has worked pretty well. Cold starts burn a fast hot kindling & small stuff fire to start heating it up and establish a coal base before trying to build a real fire. Close the doors as much as possible yet still maintaining a robust fire. When you first close the doors don't latch them to allow enough air to keep combustion going but reduce the amount of room air going up the flue keeping it cool. Latch the doors when combustion can be maintained. Slowly reduce the air supply. I go from full open to 3/4 open to 1/2 open, 1/4 open, 1/8 open, fully closed. Sometimes there's a big wait before it's ready to go from 1/2 to 1/4 open.
The outside edges of the doors get pretty goobered up, I believe due to the front of the firebox being so much larger than the back (and possibly my impatience wanting to get it closed up and air shut down). The left side is worse than the right because the air comes in on the right.
It burns much better with north/south loads, but that involves cutting to 12". I have been doing this but still have 16" inventory too. Overnight loads for long burns are full n/s, daytime loads or when I don't need as much heat I'll use 2 small diameter n/s runners on each side of the andiron and load 16" e/w on top (but don't go tight to the back). N/s fits a lot more wood. E/w be careful nothing can roll against the glass. N/s I can get 4-6 hours out of a load of pine & aspen and 8-10 hours out of a hardwood mix (depending on the mix and heat requirements) and reload on decent coals.
Outside air temperature affects draft a lot too. Even with the easy breathing NC30 at home the difference between 40 and 30 is noticable.
I was told by an SBI tech that the air comes in the right side intake to a control box that the slide regulates. There are supposedly 2 holes in this control box. One the slide covers/uncovers to regulate air to the andiron, the other hole is not regulated and supplies air to the air wash and secondary tubes. This box can be accessed by removing the screws that hold the slide assembly plate on the front of the fireplace. I never pulled mine off to look at it.
I have an outside air kit on my Stratford 2 up in the Northwoods and it is not an easy breather with it. The fireplace and flue have to be HOT for it to draft well even with 19' of straight up flue, and that's a lot of steel to heat up. It takes forever for the rheostat to kick the blower on automatically so I usually turn it on manually when it starts to give some heat then switch it to auto once it will stay on there. It stays on for a long time on auto even after the fire has died down, but if it kicks off again it takes forever again to kick back on automatically. There must be a big temperature difference in the on/off settings of the rheostat.
I was given advice on getting it going by an original Stratford owner that has worked pretty well. Cold starts burn a fast hot kindling & small stuff fire to start heating it up and establish a coal base before trying to build a real fire. Close the doors as much as possible yet still maintaining a robust fire. When you first close the doors don't latch them to allow enough air to keep combustion going but reduce the amount of room air going up the flue keeping it cool. Latch the doors when combustion can be maintained. Slowly reduce the air supply. I go from full open to 3/4 open to 1/2 open, 1/4 open, 1/8 open, fully closed. Sometimes there's a big wait before it's ready to go from 1/2 to 1/4 open.
The outside edges of the doors get pretty goobered up, I believe due to the front of the firebox being so much larger than the back (and possibly my impatience wanting to get it closed up and air shut down). The left side is worse than the right because the air comes in on the right.
It burns much better with north/south loads, but that involves cutting to 12". I have been doing this but still have 16" inventory too. Overnight loads for long burns are full n/s, daytime loads or when I don't need as much heat I'll use 2 small diameter n/s runners on each side of the andiron and load 16" e/w on top (but don't go tight to the back). N/s fits a lot more wood. E/w be careful nothing can roll against the glass. N/s I can get 4-6 hours out of a load of pine & aspen and 8-10 hours out of a hardwood mix (depending on the mix and heat requirements) and reload on decent coals.
Thanks for all the good info. My experience in running the fireplace has been very similar to yours. I've only been using the fireplace through last winter and the start of this season. So still dialing things in a bit. I thought I had my technique pretty well figured out until this week when it was struggling to burn hot and clean. After inspecting everything I believe my issue had to be the wood. It's the same wood I've been using so far this year without issue so I was thinking it must be related to the fireplace itself.
My goal is to get a couple of years ahead on my wood supply, but right now I'm having to burn stuff that I just cut and split late last winter. Mostly standing dead Ash and Red Oak that was dozed out when we were building our house. I had been checking some of the wood with a moisture meter on fresh splits and it was showing between 16-20 percent. So i thought I was doing okay. I checked some other pieces this morning and found a few at almost 30 percent. Some of the splits may have been on the North side of my bins and not dried out as fast or something like that. I think I somehow loaded up the fireplace with a bunch of the wetter splits. I'm going to have to be more diligent and check the wood more carefully.
The way we utilize the fireplace also has me doing more cold starts than re-loads. I'm guessing that's part of my occasional struggles too. I did a re-load today with well seasoned wood and it is cooking along great.
My goal is to get a couple of years ahead on my wood supply, but right now I'm having to burn stuff that I just cut and split late last winter. Mostly standing dead Ash and Red Oak that was dozed out when we were building our house. I had been checking some of the wood with a moisture meter on fresh splits and it was showing between 16-20 percent. So i thought I was doing okay. I checked some other pieces this morning and found a few at almost 30 percent. Some of the splits may have been on the North side of my bins and not dried out as fast or something like that. I think I somehow loaded up the fireplace with a bunch of the wetter splits. I'm going to have to be more diligent and check the wood more carefully.
The way we utilize the fireplace also has me doing more cold starts than re-loads. I'm guessing that's part of my occasional struggles too. I did a re-load today with well seasoned wood and it is cooking along great.
Ash split last winter should be pretty good, oak split last winter will still be pretty wet. Try to just burn the ash and you will be ok.
Burn the ash, skip the oak for now. Ash is considered a 1 year seasoning wood and will ignite and burn pretty good even if not quite fully seasoned. Oak is considered a 3 year seasoning wood that can be sluggish even at 20%. Oak has more BTU's (depending on which charts you are looking at...) and coals longer than ash, but it's gotta be seasoned.
3 years ahead is the goal, but until you get there focus on quick seasoning woods. Find BTU charts with approximate seasoning times. Ash and cherry are good mid grade hardwoods that can be ready in a year. Beech is a premium that can be ready that quick but I don't think you have much if any in Missouri. Lower grade stuff like pine, aspen, basswood, silver maple and box elder season quick and are great in shoulder season but aren't long burners. Pine is listed as 6 months and is fine to burn in modern stoves if seasoned. Other maples, birch, locust are 2 years.
3 years ahead is the goal, but until you get there focus on quick seasoning woods. Find BTU charts with approximate seasoning times. Ash and cherry are good mid grade hardwoods that can be ready in a year. Beech is a premium that can be ready that quick but I don't think you have much if any in Missouri. Lower grade stuff like pine, aspen, basswood, silver maple and box elder season quick and are great in shoulder season but aren't long burners. Pine is listed as 6 months and is fine to burn in modern stoves if seasoned. Other maples, birch, locust are 2 years.
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