Lopi Primary, Secondary Combustion Systems

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Martin D2

New Member
Apr 27, 2024
14
Ont Canada
Have a Lopi Med Flush Wood Insert. I persevered over 1 winter, learning to operate it, and while I did get some heat, I suspect I never achieved the secondary combustion, explained in the manual and comments here. Page 22 of manual says the air control supplies air to the air wash above door opening OK, and through the primary pilot orifice centre bottom door opening. That I cannot find, even even removing bottom fire bricks. Where is this hole? How big is the orifice? It also cautions not to block this orifice when adding wood.

The air control slider, I cannot see the rod attached to any valve though it obviously is, Removing the front face of the insert did not reveal any orifice or valve.

What is needed in this complicated technical setup is a schematic drawing of the primary/secondary combustion systems I see the secondary air tubes, the primary intake is the problem.

I have experimented with the air mixture many times, and it does reduce the burn rate, but usually too much. I find with a hot bed of coals and the air mixture full in, high burn rate, a reluctance to ignite. There is no aggressive bottom draft. Typically I try this before bed time. Playing with the door, or using a bellows will ignite the new wood load but I really shouldn't have to do this.

I have read the explanations and understand the technical details, though I am unable to operate the system as outlined in the manual. A technical diagram would be of great help, also very easy to do. but I have never seen one.
 
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The description seems to indicate that the wood was not fully seasoned though weak draft could also cause some of these issues.
 
The wood is very well dried. The weak draft is the problem, but that is my question with the primary pilot orifice.

How did you verify that the wood is very dry? Has it been split and stacked for over a year? How tall is your chimney?
 
How did you verify that the wood is very dry? Has it been split and stacked for over a year? How tall is your chimney?
Cut and split for a year and 1/2 now, checked with Travis supplied moisture meter. My chimney is over 30 ft. From the get go, the problem has been no aggressive bottom draft, a desired priority fro me.
 
Cut and split for a year and 1/2 now, checked with Travis supplied moisture meter. My chimney is over 30 ft. From the get go, the problem has been no aggressive bottom draft, a desired priority fro me.
Is this a basement install? If so, it may be a negative pressure zone. If the chimney is exterior, this can lead to balky performance. Have you tried opening a nearby window an inch to see if that improves starting and performance?
 
Is this a basement install? If so, it may be a negative pressure zone. If the chimney is exterior, this can lead to balky performance. Have you tried opening a nearby window an inch to see if that improves starting and performance?
No it is on the main floor, a 2 story house, so the chimney is exterior and high, and with the stainless liner. It was installed by a pro, at least a licensed worker, fits all local regulations. Only a year old, it worked like this from day 1.
 
The main floor can still have negative pressure, especially if there is an air leak on the second floor through a attic door, attic vent, bathroom vent, or leaky windows. Try opening a nearby window 1/2" and see if it make an appreciable difference.

Was the wood first split in half and then moisture tested in the middle of the face of the freshly exposed wood?
 
Yes tried a window open; and the wood is definitely dry. some of it is kindling dry, no real difference. My original question about the primary hole: If it is plugged slightly that could account for it. But, I cannot see it, to clean it out. Plus the problem was there from my first fire a year ago.
 
Normally the suction in this setup would pull very strongly. Is the bypass opened each time the insert is started?

Is there a 30' long 6" stainless liner connecting the insert? One possibility could be a kink or bend in the liner. Has this been inspected and cleaned, including the chimney cap screen if there is one?
 
Yes the bypass works as directed. The setup is brand new including the stainless insert. The prob;em was there from day 1, and the dealer installer has went out of business. Still I did inspect and clean the tubes as best I could. It does work, just not very well with the air mixture pulled off a bit.
 
Yes the bypass works as directed. The setup is brand new including the stainless insert. The prob;em was there from day 1, and the dealer installer has went out of business. Still I did inspect and clean the tubes as best I could. It does work, just not very well with the air mixture pulled off a bit.
Get another professional in to check everything out. It has to be lack of draft (which at 30' you should have to much draft) or poor fuel. The fact that it is hard to light even with the door open tells me it's not the controls. What species of wood is it? What was your procedure using the moisture meter? What was the reading you got?
 
OK I found the pilot hole, less than 1/8 in near the top of the hump under the door, Cleaned it out with a pipe stem cleaner, though it wasn't plugged, But it could be covered with ash, which the manual mentions. Did not see how the mixture leaver works, the valve must be further in the body of the stove. That size hole would not allow a huge amount of bottom draft, which is what I am seeing. Cleaned all the visible draft holes will try a fire again tonight.
 
OK I found the pilot hole, less than 1/8 in near the top of the hump under the door, Cleaned it out with a pipe stem cleaner, though it wasn't plugged, But it could be covered with ash, which the manual mentions. Did not see how the mixture leaver works, the valve must be further in the body of the stove. That size hole would not allow a huge amount of bottom draft, which is what I am seeing. Cleaned all the visible draft holes will try a fire again tonight.
Go get a couple 2x4s cut them up and see how it works with them
 
Such a small pin head pilot hole, there is no aggressive bottom draft, the draft comes from air wash above the door. Sticking a wire in the pilot hole does not effect the air mixture control, it can be moved in and out freely. I still would like to see where that air control valve is. It would help me understand how the system works and what I can do to control the fire better.
 
Such a small pin head pilot hole, there is no aggressive bottom draft, the draft comes from air wash above the door. Sticking a wire in the pilot hole does not effect the air mixture control, it can be moved in and out freely. I still would like to see where that air control valve is. It would help me understand how the system works and what I can do to control the fire better.
Did you try burning some 2x4s cut up to eliminate poor fuel? Did you have a different pro out to.check things out and maybe test draft and run the stove a little?
 
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Such a small pin head pilot hole, there is no aggressive bottom draft, the draft comes from air wash above the door. Sticking a wire in the pilot hole does not effect the air mixture control, it can be moved in and out freely. I still would like to see where that air control valve is. It would help me understand how the system works and what I can do to control the fire better.
I don’t understand what your obsession with the bottom draft is. The main intake air on modern stoves comes from the air wash. The secondary air is fed from a non controlled air feed to the top tubes.
 
Did you try burning some 2x4s cut up to eliminate poor fuel? Did you have a different pro out to.check things out and maybe test draft and run the stove a little?
I have eliminated wood as being any part of problem, have a variety of fuel including 85 yr old cedar rails. It is the draft or lack of it. I have no access to a technician, mine went out of business soon after installation.
 
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I have eliminated wood as being any part of problem, have a variety of fuel including 85 yr old cedar rails. It is the draft or lack of it. I have no access to a technician, mine went out of business soon after installation.
And there are no others in your area?