My pursuit of the All-Night Burn! (Hampton HI-300)

I purchased a Hampton HI300 insert with the brown enamel finish last fall. I've been very happy with the unit, but I wasn't getting the burn times I was hoping for. Usually the unit was cold by morning. I knew part of the problem was my wood. The seller said it was "seasoned", but as many people on this site have experienced, it wasn't up to snuff. About half the splits were "juicy", meaning water bubbled out the end grain as they came up to burning temperature in the stove.

So last April I cut my own wood out of the State Forest along the coastal mountain range here in Oregon. A $10 pass gets you up to two cords. Well, $10 plus $120 for new safety gear the wife insisted on, plus $40 in gas, plus $30 for lunch at Dairy Queen for me and the kids, plus a stop at the beef jerky shop, plus miscellaneous chainsaw expenses. Ended up being the most expensive "free" wood ever! But I loved doing it. And the kids won't admit it, but they liked it too.

It's all douglas fir up there, so I was a bit concerned about getting good burn times out of it. On the plus side, the wood I got must have been down for a year or so because it was already dry. I burned some of it immediately after cutting and it was way better than the "seasoned" stuff. Now, after drying all summer it's excellent.

Last night I fired up the Hampton from a cold start at 6:30pm with a moderate load and let it cruise until 10:30pm at which point the glass temperature was reading about 450 and I was looking at a medium size bed of coals. I would have let it go another hour or so, but I needed to get to bed, so I raked the coals forward and loaded 4 large splits and one medium split E-W with the largest split (about 8" diam) in the rear of the firebox. The new load took off right away and I had the air choked back to about a half-inch open within about 15 minutes. That's the most I've ever choked it down, for fear of creosote, but after watching it burn so nice I am confident that with the strong draft of my chimney, plus quality dry wood it's fine. The glass temp. peaked somewhere around 700-800F (I wasn't watching it too close) which is pretty normal for a full load on a hot bed in my unit. When I went to bed around midnight the glass temp. had settled in around 700, maybe a little hotter and was on a slow decline. I had a low level of bluish wispy flames like aurora borealis wafting through the firebox. It looked great.

Woke up this morning at 6:30am to find the automatic blower still on, glass temperature around 250F, and not a lot, but enough coals that I just tossed on 4 more medium splits and with 15 minutes it was back up and running just fine! Success! An 8 hour burn on douglas fir!

Here is my recipe for the all-night burn.
1. Use dry wood.
2. Use large splits.
3. Shut the air way down. Looks like I can get away with shutting it almost completely off with my new dry wood.
4. Rake the coals forward and set the splits E-W with the largest in the rear of the firebox.

I know there's nothing new there, just a confirmation that the advice all the old-timers on this site give really works. I thought fellow Hampton HI300 owners who are learning to run their stove might like to know that the 8 hour burn time claimed in the HI300 specs really is achievable. Heck, if had oak to work with I think I could have made it to 10 hours! That'll be my next project.
-Jim

One more piece of learning I picked up: I use an infrared thermometer (Kintrex IRT0421) to get the temperature, and I mostly use the glass temperature as my reference. Turns out that the infrared thermo. picks up the glass temp., and not the temp. of the fire itself. You can try it out and see for yourself. The temperature reading you get depends on where the laser sight hits the glass, and not what it's pointing at inside the firebox.

Someday I hope to be able to say the same thing. I've got a HUGE oak tree on my property, but it's an integral part of the landscape . . . can't cut it down. But if a storm came along . . .! Maybe just a large branch or two?

I've got some cherry that's been drying for almost a year. I'm saving that for the colder weather. Maybe I can stretch it to 9 hours or more.

This infrared thermometer is what I have.
http://www.amazon.com/Kintrex-IRT04...9Q9C/ref=sr_1_3?ie=UTF8&qid=1318038007&sr=8-3
Works great for me. I think it's reasonably accurate. More importantly, it is very repeatable. I check the temps on the glass, and I've learned by experience what to expect based on the readings - that and just looking at the fire itself.

Jim
P.s. Oh yeah . . East-West loading refers to side to side, and N-S loading is front to back. I prefer N-S loading in general for convenience, and no worries about logs rolling forward to hit the glass. But for longest burns, e-w seems to be the best.

More info about thermometer usage: I usually shoot for the temperature to level out in the 700-800F range, and it will cruise along there for a decent while before starting a long descent. I've run it as hot as 900F with no sign of problems - collar not glowing red, not even a little. The secondary air tubes will glow red for me when the glass temp is above 700F. Keep in mind that you shouldn't rely too much on the absolute temps I am quoting. You just have to watch your own stove close for a couple of months until you have a good feel for how it behaves w.r.t. The temperature readings.

I don't know for sure, but it seems like pulling th coals forward and loading big splits in the rear sets up a situation where the fire burns to the back over time. By not setting them down directly on a bed of hot coals, you delay their ignition, thereby prolonging the overall burn time.

UPDATE! 9-10 HR BURN TIME ACHIEVED!
Last night I tried a mix of Doug Fir and Cherry and I choked it down more than ever. Reloaded at 9:45pm. This morning at 6:45am, glass temp. still at 340F, plenty of coals, even a tiny wisp of flame, automatic fan still on! That's 9 hrs, baby! A new record for me. I'm sure I could have stretched it to 10hrs and still would have been able to toss on a couple of medium splits and had it going again, no problem.

So 9-10 hours is doable.

I did end up with a bit of a haze on the glass, which I didn't get last time. Not bad really, and it will burn off just fine on the next fire. I'm sure this is a result of closing the air supply down so much. I had it just about a quarter inch open.

-Jim