Lopi Republic 1750 review & comment on not understanding how my stove heats (itself, not the house)

I've had my Lopi Republic 1750 long enough for about 4 days of 24/7 (or near) burning and about 10 total days of fires.


Bottom line
Great stove, absolutely love what it's doing for us already and its showing that it can heat a 2200 square foot 2-story colonial house to an acceptable degree down to 30 degrees outside. (hasn't gone lower than that yet). The main living space is easily 75, and the rest of the house is probably mid 60s. Completely acceptable to me if I can maintain that down to 20 degrees and augment with small oil-based electrical radiators when additional spot heating is desired. Price for stove with all black trim, 10" surround trim, mantel shield, and blower was under $1800. Installation with a 15' length of insulated 316ti steel liner by a chimney sweep was $1100. Though it's an economy line, it has a very quality look to it and is aesthetically pleasing, if simple.

Successes
With a good fire it'll heat up ridiculously fast. For example, this morning I had a small bed of coals left over from last night's burn. Stove top temp was about 150 degrees, thermostatically controlled fan was off. I went outside and picked up 2 3" wide, 18" long splits and a bunch of kindling as well as 2 5" splits.

I stacked the smaller splits + kindling in there and it lit itself off though I augmented with 3 crumpled sheets of newspaper. Bam, lit up instantly. 10 minutes in, the kindling was mostly solid coals so I stuffed the 2 5" splits in there on top (up to the air tubes, but overall the stove was only 50% full).

Within 25 minutes from putting the kindling in, I had gone from 150 degrees to 650 degrees. I cranked the fan all the way up, closed the air control down, and it just hummed along at 600 degrees for another 20 minutes until I left for the day. Was about 35 degrees outside during this period. Wood is probably 25-30% moisture content.

Secondary Burning

Oddly, I've had plenty of fires humming along at 450-650 degrees, damper closed and air control in every position (closed, fully open, half way, etc.)....and I almost never get true secondary burning. Oh, I get some flames licking around up there, and sometimes I get the beautiful aurora borealis-like slow moving flames that grow downwards. But I have only once seen genuine full secondary burning (ironically, on my first fire in the stove when it was like 350 degrees and I shut down the damper and air control at the same time; haven't been able to dplucate that).

I don't understand it honestly: I've had ALOT of scenarios now, including 700 degree near overfires, 350-400 degree hours-long smolders, and healthy newer 500-600 degree roars.

As a side effect, I'm not getting the air wash on the glass seen in this video: http://www.youtube.com/watch?v=b4No-WL1Wmk

Also, I think I'm getting much faster burns because it's not entering into a slow-burn secondary combustion stage.

Weird stove top heating

I have a Rutland stove top thermometer. I'm sure it's not 100% accurate, but it does seem consistent.

Getting the stove up to 300-350 degrees on the Rutland is no problem. I can do it now everytime, consistently, and with a healthy fire. But what I don't understand is that it'll be cruising along at 350 degrees with a good bed of coals and no real active flaming logs. I'll open her up (damper, air control, and door) and stock it well with plenty of air spaces with good, reasonably-sized ash splits that are probably around 25% MC.

They'll light up quickly and I'll shut the door. They'll get engulfed and I'll shut the damper.

And then the stove rises quickly to 400 degrees....and stops. Just hovers there. I've had this happen about 4-5 times now. It's a definite pause in the thermometer; once I know its paused, I'll do stuff like re-position the wood, add more wood, give it some more air, etc.....the burning intensity will increase, maybe I'll get another 20 degrees out of it, but that's it. And then it'll go back down to 400.

Now 400 degrees is nice and comfy, but I don't think it'll be enough to provide good all-around heating when it's 15 degrees out. I need to be able to take a good, stable, strong bed of coals at 350 and bring it up to 600 quickly...but I can't find the knack yet. I blame myself, but I don't understand it when on days like this morning I can get it up to 650 degrees in 30 minutes off a weak coal bed and ice-cold wood with morning dew on it.

Stove Pinging, cracking, and creaking

I didn't notice this at all durign the first few fires, but now my stove pings, cracks, and creaks whenever it's heating up quickly. I first found it disconcerting, but it seems perfectly normal. Some can be a tad loud (it would wake you out of a nap), but its only when you've just started it or just adjusted it to heat up quickly. By quickly I mean like 100 degrees in 10 minutes or less (i.e. going from 300 to 600 degrees in 20-30 minutes).

Once it's at temp, heating slowly, or cooling slowly, it barely makes any sound. Hell, the box is so well insulated and the door so well sealed that you literally can't HEAR the fire when the door is shut and only rarely do I hear a log crack. Open the door and the sound hits you.

While I enjoy a crackling fine, I've found that I like how quiet and unobstrusive it is to have a fire going 10 feet from where we're watching TV. Once the fan is on, that's all you can hear anyway....it's a nice white noise, definitely noticeable when it's on medium. On high, it's loud. But damn if it ain't moving some air too.

...

Love to hear any thoughts.

Oh, I'll add that I've tried top down lighting and a few variations already. Everything worked, but by far the best working setup was to place 2 3" splits in a V with the open end facing the door (N-S this stove is about 23" deep). Then criss-cross the V with lots of kindling and build it up to about 2/3rd of stove height. Then put 3 pieces of crumpled newspaper on top and 2-3 underneath the kindling. Door opened a crack and in 10 minutes you'll hit 300+ degrees from a cold stove and be ready to add some bigger pieces. Let the big pieces light off, close the door, ensure everything looks strong and then close the damper all the way. 600+ degrees in under 30 minutes.

I can't get secondary burning to be going nuts, but I can do that consistently at least

Joefrompa thats a video I put up last year and I think I shut it down for a overnight burn once I hit 500-550 with good coals, after shutting it down it can jump 75-100 degrees depending on the wood I'm burning. The wood I was burning was between 18-20 percent moisture content.


zap

I have a Jotul Rockland C550 wood burning insert and have not yet gotten a secondary burn. Also I have a center hall two story colonial and the house thermostat is in the DR across the center hall from the LR where the insert is located. My house never seems to go more than 5 degrees up from where it starts. The LR is plenty comfy, but thats where the insert is. It also seems warmer upstairs in my room. I dont have a thermometer yet. Dont know what kind to get in light of the fact that the insert is flush to the bricks. Any suggestions. The Insert seems only to have an air control lever. I would appreciate any thoughts.

One of the things I'm completely accepting of, and watching, is that heating a cold 2200 square foot house with a 2.2 cubic foot firebox is difficult. You'll get the immediate space toasty in less than an hour, but the bedrooms and such? Maybe 3-4 hours to start feeling meaningful heat up there.

On the flip side, once you have the house toasty its not hard at all to KEEP it warm or raise the temp by 3-4 degrees (net). Letting it get cold is a killer.

Regarding the thermometer - You can get the most accurate kind, an Infrared device (about $40-50 for a decent one) that you point and click. Gotta tell you, alot of stove top thermometers are $20 and not that easy to see and you need to get up each time, so a little infrared might be nice. Just point it at the top of the door above the glass IMHO.

....

Btw, using your Jotul, are you using a blower, how about fans?

Zapny - That's pretty funny. Sorry I didn't know to source you.

So you are saying that you achieve 500-550 (I'm guessing with damper shut) then you close the air control and get those secondaries + temp spikes of up to 75 degrees AFTER shutting down, or is that because right prior to shutting down you stocked the box?

Joe

My Endeavor has the same fire box. I have a hard time getting it to "cruise" under 600F with the blower off. It levels out around 500F with the blower on low. And for what it's worth, I can't completely shut the primary air on my stove all the way down and maintain ANY active combustion, primary or secondary. I leave the control open around 1/4" or so and it cruises along just fine.

Yes the Rockland C550 has an automatic fan that goes on when the stove reaches a certain temp. Im not sure what temp that is, LOL. I guess I should find that out., duh!!

I was told by Travis Industires for the Lopi Liberty I would get better secondary burns around 600, when you say damper are you talking about the by-pass if so yes it's closed plus the air control is closed.

Yes the temp on the Liberty will spike after shutting it down for a overnight burn, that is why I'll stay until it levels off at a certain temperature before I call it a night.



zap

Pagey - Actually, that's a valid point I wasn't addressing. This fan moves some serious air in my opinion (far more than my in-laws Jotul Kennebec blower). When I can't get it above 450 degrees, the fan is and has been on medium to medium-high and I don't turn it down.

I didn't think that could suck THAT much heat out of the firebox as to prevent the stove from rising much higher even with alot more fuel added, but it is one of the differences between when I can achieve 600 and when it doesn't rise above 500 no matter what I try....I've been achieving 600 on NEW fires where the blower is either not on for awhile or on low, whereas I haven't been able to get existing fires to pump up above 500 but the fan has already been on medium medium high and I haven't changed it...

Yes, sorry, by damper I mean by-pass control. I usually have that closed as soon as the fire is strong and stable (usually 2-5 minutes after first closing the door). It doesn't seem to hurt the fire at all by that point, and the stove temps soar with the bypass closed.

Ok, I'm going to see if I can get it up to 600 degrees with the bypass closed and air control full open, stock it, then shut the air control and see what happens....

Joe I keep the by-pass open until I get the flue temp 400 then I shut the by-pass and after my first load which is 3-4 splits I let the coals burn down to a stove top temp of 300-350 then reload which seems to work for us.

The secondaries will kick in once you establish a good bed of coals and a reload, last year I was burning smaller splits because it was not seasoned a full year which will make it burn hotter.

Each stove and setup is different so what works for us might be different for you.

zap

joefrompa, these are some emails from travis about the liberty and the temps.

Mike,

That stove is going to do the best in the range of 400 degrees +. You want to get it hot during the initial fire so when you go to close down the bypass the combustor will work as designed and create a secondary burn.

Mike,

I would suggest putting a stove thermometer on the stove top. That particular unit has a low burn of 200-400 degrees, a medium burn of 400-600 degrees and 600-800 degrees is considered a high burn. A good range to burn at is between 350-550 degrees. I am ready for winter as well so bring on the cold weather!

Sent: Monday, September 21, 2009 8:13 AM
To: Hale, Christian
Subject: RE: Lopi Liberty

http://www.travisindustries.com/contacts.aspx

zap

Keep us posted, I'm curious.

The blower, in my experience, can make a dramatic impact on stove top temps. I have no problems getting to a 600F stove top on the first fire of the day, as it takes the blower quite some time to come on. My stove will cruise at 600F for 15-20 minutes, usually, before the blower comes on, and I always run it at low as I find that moves a good amount of heat with the least amount of noise.

When I rekindle a fire, I turn the blower off completely until the stove reaches 600F again for at least 10 minutes. This way, I only pull the surface temp down to about 500F and seem to get more convection heat from the unit.

Your questions here are kind of buried in Joe's thread . . . you might have better luck asking these questions in a thread of your own . . . specific to using an insert.

However, just because I'm a nice guy and don't want to be a jerk . . .

Thermometer: You can try using an IR thermometer -- you can pick one up at Harbor Freight . . . or you can use a magnetic mount thermometer for the front of your insert.

There are a lot of threads about how to achieve secondary combustion, but here's the Cliff notes . . . you need to have a decent load of wood in the firebox . . . and this wood should be well seasoned . . . you also need to bring the temp up in the firebox hot enough so you can get the secondary burn . . . time is a big factor . . . if you've had the stove going for a while it is far easier to get a secondary burn faster than it is to start a fire and expect a good secondary burn within 15 minutes.

My advice . . . load the stove, leave the air open, leave the door ajar a bit . . . and get an IR gun or magnetic thermo . . . when the fire is really cooking shut the door to the stove (this is where it would be handy to have a thermometer since other insert owners could say when the insert reaches X degrees shut the door and when it reaches Y degrees start to dial back the air control).

However, in the absence of these useful devices . . . let the fire roar nicely for a bit and then try closing the air lever just a bit (3/4 of the way shut) . . . wait . . . and observe . . . is the fire still burning nicely after 5 minutes or is it starting to die down and suffocate . . . if it is dying down, open the air again and let the fire get roaring again for another 5-10 minutes and then repeat . . . if the fire continues to burn nicely after 5 minutes turn down the air to the half way mark and again wait and observe.

At some point you will find the fire continues to burn . . . but now it is also burning in the upper half of the firebox . . . and if things are hunky dory you will soon be rewarded with a magical unicorn . . . I mean an intense secondary burn . . . which should provide more heat to your home and dazzle your visual senses . . . I should add that you will want to turn down the air control to the point where the secondary burns well without suffocating the fire -- for me this is usually a quarter way open or even all the way shut . . . the secondaries should still be doing their magic, if you go outside you'll see no smoke coming from the chimney and inside you will find you have a longer burn and a lot more heat coming out of the stove. Oh yeah, I don't have an insert, but I imagine at some point you will want to turn on the blower.

How you liking that stove, Joe?
We just reloaded ours tonight, (last wood in probably 10pm last night) and relit from coals only. I assume that there's got to be effective heat coming from the stove for that to count as a 20+ hour "burn" but it's still pretty neat not to have to relight. I would say it put out effective heat maybe 9 or 10 hours though for sure.

Yesterday the house got too hot, so I let it all burn down to ash without reloading, and the blower kept blowing and the heat kept coming long after the wood was effectively gone to coals for quite a while. House remained at 74 or so. I know it's not TRULY cold out here yet, not in VA, but I'm totally pleased not to have the dang heatpump on, and to have the house so nice and toasty. The heatpump NEVER feels toasty.