New Lopi Answer- Questions

  • 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.

Rose Lane

New Member
Nov 5, 2021
31
Maine
This June 2021 manufacture Lopi Answer is the only heat source in this 350' off grid workshop. I'm having problems getting the fire burning on a daily basis and if the space was unused prior day, (and thus cold) it can take 6 hours to get the space up to a reasonable low 60s working temp.

We have been using exclusively kiln dried wood; and have plenty of experience with wood heat. Wood stoves are our only heat source in two other structures, including our home.

It takes me (and my husband too) about 30 minutes with the door open to get the fire to burn. If the door is closed prior to that period of time, the fire goes immediately to smoldering. Black-blue smoke comes out the chimney.

If the workshop is cold (sub 30 degree) in the morning, it takes 6+ hours to get the interior temp up to comfort zone.
Everything about the setup is new this year: new structure, 6" rockwool insulated walls, insulated roof, new chimney, new stove, kiln dried wood.

Any suggestions? it's really interfering with my work to be so cold all day. 🤓

stove.png studio.png
 
Oct 13, 2020
144
Quebec, Canada
How tall is your chimney and is it insulated ? Normally require about 15 feet of chimney height from stove top for proper draft and for stove to work properly although from the photo the fire seems to be burning well in there.
 

ManitobaSky

Member
Nov 20, 2013
67
Manitoba, Canada
This is the second stove you have had issues with in the same space correct? What are the offsets in the double wall, 2 x 45 elbows? That would reduce your height by 2 feet or so what could be pushing you into a low draft situation. Also when you are saying kiln dried wood, that might only mean that it’s been heated to kill bugs and not really kiln dried, have you tried using dimensional lumber like 2x4‘s and seeing if that makes a difference?
 

Rose Lane

New Member
Nov 5, 2021
31
Maine
This is the second stove you have had issues with in the same space correct? What are the offsets in the double wall, 2 x 45 elbows? That would reduce your height by 2 feet or so what could be pushing you into a low draft situation. Also when you are saying kiln dried wood, that might only mean that it’s been heated to kill bugs and not really kiln dried, have you tried using dimensional lumber like 2x4‘s and seeing if that makes a difference?
Correct. Second stove in the same space.
The reason I don't suspect a draft issue is that when trying to get the stove going- with the door open- smoke doesn't come into the space. It seems more like stove was designed with too little airflow.
I have tried dimensional lumber, it seems worse actually (which shocked me too). The wood was sold as kiln dried; $375 per cord- burns fabulous in our other two stoves.

Tomorrow morning I'm going to actually moisture test every single piece I put in and keep tabs on the chimney surface temp. Will post those details. I'll make photos of the offsets tomorrow.

Regarding how long it takes to heat up the space once the stove is going- I know there are a lot of factors that come into play but 6 hours just seems insane for a small newly insulated 2x6 rockwool space. This particular stove is rated for 1400 square feet I believe. Ever seen any good calculators that help one figure out how long and how many BTUs it should take to go from x temp to x temp within a space with x windows?

My husband's workspace (small: 144 sq feet, only two windows) heats up in under an hour. Old Vermont Castings.
 

ManitobaSky

Member
Nov 20, 2013
67
Manitoba, Canada
Should not take 6 hours to heat 350 sq./ft. !
Agreed, even if cold that space should be warm in way less time.

The chances of getting two different models of stove showing the same issues in the same space makes me believe the stove is not the issue or at least not the only issue you are dealing with. Remember when checking moister, the wood should be room temp and checked on a freshly split face and try and get the probes as deep as you can into the wood.

Also how are you storing the wood once you get it, covered outdoors etc.
It is completely possible the wood works fine in your other stoves and still maybe less then optimal. Some stoves are “easy breathers” and if they have a taller flue they would be more forgiving of damp wood.
 
Last edited:

PaulOinMA

Minister of Fire
Oct 20, 2018
1,126
MA
I use 1 1/2 sheets newsprint, kindling and firewood. No issues with starting.
 

MR. GLO

Member
Jan 26, 2021
235
Massachusetts
Most kilm dry wood is not oak because it costs them more time and money to get it down in moisture content.....lots of kiln dry wood is mixed too...they rush the loads in and out.

I would start the fire with only kindlin.. and then add the wood.

Once you get the stove going and reload count how long it takes to start to flame on hot coals.
One minute is good 3 minutes I'd bad.


Sometimes even home depot kiln dry bags are wet and not ready.

Invest in a draft guage. We need stt and flue temps to help troubleshoot...
 

MR. GLO

Member
Jan 26, 2021
235
Massachusetts
Also if you cant get a draft guage soon, take off the cap and test
 

Birkie

New Member
Dec 15, 2021
10
Wisconsin
Rose, you mention it seems like too little airflow once burning. With the new insulation, your workshop is more air-tight. I wonder if you need to provide a fresh/outside air supply directly to the stove? I just finished a restoration of a 1995 Lopi Endeavor and connecting the fresh air vent is giving me amazing control and clean burning in my newly constructed "tightly-sealed" home. No puffs of smoke, a bright fire, and it heats up my 1320 sq ft quickly. Perhaps the shop you bought the stove from could advise you.

You could buy Lopi's fresh air supply system for $160. Or I made my own kit with the same components for $44 and got a 4" supply.

Fresh air connection at stove.jpg Whole stove installation.jpg
 

Attachments

  • Fresh air supply list.pdf
    112.9 KB · Views: 6
Last edited:
  • Like
Reactions: stoveliker

stoveliker

Minister of Fire
Nov 17, 2019
2,784
Long Island NY
Good suggestion. Do you think things noticeably improve when you crack a window? That'd be a telltale sign.
 
Last edited:

MR. GLO

Member
Jan 26, 2021
235
Massachusetts
You could use that draft gauge (maybe borrow one) but you could get a permanent Magnahelic for the same price and more accurate measurement. You will want to see the draft during the burn cycle. But first I would get a flue probe and stt gauge and try kindlin and get co2 smoke detector and lets see the temps.

Then take the cap off and see what happens with temps on stove. Do you also get smoke in room on startup? Sub 30 degree is a cold room to start.

Once you determine if you are.reaching stt and flue temps and eliminate the wood issue...

then my guess you need a bigger stove. The btu on that stove is 59k but your weather conditions are 'very cold"....do you know anyone near you with a room like yours and heats it from a start?

20220115_085559.jpg Screenshot_20220115-085152_Nest.jpg
 

Rose Lane

New Member
Nov 5, 2021
31
Maine
Using the calculators on this page, I got some estimates for what the space should require:

9000 BTU to heat
27k BTU to increase 50 degrees (i.e. 20 degrees to 70 degrees, which is a typical requirement)

Now, does this mean it *should* take 3 hours to come up to comfort zone?

The Lopi Answer spec says:
EPA Tested BTUs: 12,129 to 59,527 (CORD WOOD) (per load of wood)

Obviously, that is a huge range, but implies that I could be getting at least 12k BTUs out in the first hour, right?

BTUs.png timeto heat.png
 

Rose Lane

New Member
Nov 5, 2021
31
Maine
You could use that draft gauge (maybe borrow one) but you could get a permanent Magnahelic for the same price and more accurate measurement. You will want to see the draft during the burn cycle. But first I would get a flue probe and stt gauge and try kindlin and get co2 smoke detector and lets see the temps.

Then take the cap off and see what happens with temps on stove. Do you also get smoke in room on startup? Sub 30 degree is a cold room to start.

Once you determine if you are.reaching stt and flue temps and eliminate the wood issue...
Ok, sorry to have to ask: what is stt?
No smoke comes into the room during startup.
I figure all the Amish around here deal with the same issues, so I should ask them :)
Does flue probe mean I need to drill a hole into the flue? 😬
 

MR. GLO

Member
Jan 26, 2021
235
Massachusetts
Stt is stove top temp. With ir gun in several spots check temp or magnet temp guage usually near middle of stove tip or just off center. Somone with you stove might be able to give you a better permanent location.

Depends on which probe. But the manual probe yes. The auber hole is screw hole size.
hole in pip is no bid deal. You can cover with a magnet if need be but you could use the same hole for probe and temp draft tester.

That btu calculator needs to change from boston.
But all the shops in North Country nh I've been too had wood or pellet furnaces with blowers but it was toasty hot.

Please send us the stt and flue temps..
 

Woodcutter Tom

Burning Hunk
Apr 28, 2019
179
Northern Illinois
How are you measuring your 16' flue height? From the top of the stove or from the floor? To me, it sure does not look like 16' above the top of the stove. I look at the door which would be about 7' and the height of the wall inside. Seems shorter than 16' to me.
 
  • Like
Reactions: ManitobaSky

stoveliker

Minister of Fire
Nov 17, 2019
2,784
Long Island NY
Using the calculators on this page, I got some estimates for what the space should require:

9000 BTU to heat
27k BTU to increase 50 degrees (i.e. 20 degrees to 70 degrees, which is a typical requirement)

Now, does this mean it *should* take 3 hours to come up to comfort zone?

The Lopi Answer spec says:
EPA Tested BTUs: 12,129 to 59,527 (CORD WOOD) (per load of wood)

Obviously, that is a huge range, but implies that I could be getting at least 12k BTUs out in the first hour, right?

View attachment 289934 View attachment 289935

If those lopi numbers are per load of wood (as it says), that would mean you have to burn down the full load of wood to get those BTUs. Can you burn a firebox down to reload time in one hour...??

You need to look at BTU s per hour.
 
  • Like
Reactions: ManitobaSky

brenndatomu

Minister of Fire
Aug 21, 2013
6,737
NE Ohio
I hate to say this but it sounds like subpar wood.. Id check with a quality moisture meter on a room temp fresh split face.. not on end grain or on any part of the outside of the split
X2.
Most kilm dry wood is not oak because it costs them more time and money to get it down in moisture content.....lots of kiln dry wood is mixed too...they rush the loads in and out.
Most "kiln dried" firewood, is not really dry...only heated long enough to qualify as "kiln dried", which in firewood just means the bugs have been killed off and the wood can be transported out of the area. It has nothing to do with actually being dry.

There's no need to spend big bux buying a draft gauge...many of us wood furnace guys use this one, and it can be bought for under $50 all day long...sometimes much less...and its plenty accurate for using on a wood stove flue. Look for NOS and "used" ones on fleabay and scamazon...search Dwyer Mark II model 25.
 

MR. GLO

Member
Jan 26, 2021
235
Massachusetts
X2.

Most "kiln dried" firewood, is not really dry...only heated long enough to qualify as "kiln dried", which in firewood just means the bugs have been killed off and the wood can be transported out of the area. It has nothing to do with actually being dry.

There's no need to spend big bux buying a draft gauge...many of us wood furnace guys use this one, and it can be bought for under $50 all day long...sometimes much less...and its plenty accurate for using on a wood stove flue. Look for NOS and "used" ones on fleabay and scamazon...search Dwyer Mark II model 25.
Thats a good one..I bought a glass magnehilc on ebay cheaper then a new fill mark II.

But I agree I would spend money on other tools and testing first.
 

old greybeard

Member
Oct 29, 2018
92
PA
That’s a small 1.5 stove. Not surprised it takes 6 hours to heat that space at all. Especially depending on insulation. The sq ft and btu rates are for comparison, and in my experience not based on reality. Had a Lopi 1750 in my 850 sq ft cabin. 2.0 firebox. Took forever to warm up and then couldn’t maintain heat. Went to a big Osburn 2300, still slow to heat from cold compared to my old smoker, but will maintain heat when warm.
These epa stoves just don’t throw a fast high initial heat to quickly warm a cold area unless they are way oversized.