Flame shield design change. When did it sprout 'wings'?

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Derf Summerfreeze

New Member
Oct 10, 2023
31
Southern Ontario
Question for PE owners. Specifically, I have a 2022 Alderlea T6. It has a newer style flame shield with a tab welded on that obstructs the flow to the flue considerably. I presume this was done to slow the evacuation of unburned gasses to make the secondary burn more efficient for the latest EPA regs. I have plenty of draught with 36 feet of chimney up through the centre of the house and plenty of vacuum under normal conditions. The problem arises when I go to add wood to an already flaming fire. Smoke enters the room even following the usual standard practices to avoid that. I made a deflector that has corrected the issue by 60% by driving the air flow down into the fire and deflecting the flame upwards to the gap in front of the secondary air baffle. Basically it replaces the action of the airwash in directing the flow of air when the door is opened, but has no impact when the door is closed. It helps a lot but I need to do more to correct this. Any smoke while reloading is unacceptable in the long term. There are two other issues with this stove contributing to the smoke. I think the biggest one is the huge restriction caused by the new style flame shield. The second which might not be an issue with less restriction, are the side rails that extend so far forward, that the flames 'walk' under the rails and right out the door when it is opened. As a matter of fact, even with the door closed and the airwash doing it's job, the flames walk the rails and roll off the glass at each side of the window. That's an easy fix, but one thing at a time. Question: When did PE start using this very restrictive heat shield with the 'wings'? Thanks, Derf
 
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I think the change happened with the newest LE model. However, I have run the new Alderlea T6 that I helped install locally and this has not been an issue. Their stove has a 24' straight-up flue.

A 36' tall flue will present issues for almost any stove. Has the draught strength been measured on the stovepipe? It could be part of the problem. Is there a key damper on the stovepipe?
 
I have not specifically measured the draught, although I know it is exceptionally good. No extra dampers in my stovepipe either. The internal flame shield is a real choke point. I wonder if the one you installed has the older flame shield or the wings are bent inwards slightly to allow more flow. The problem in my case is not available draught, it is a restriction that is built into the stove. Under low flow conditions the vacuum within the stove cavity remains quite high due to the tall chimney (see my other post on modifying the EBT so it won't go tink-tink). It's only when opening the door with an already very active fire that smoke comes out. More oxygen in from the open door equals a quick increase in combustion that requires a less restrictive opening to the flue. If it can't go up the chimney it will take the next easiest route which is into the room. Most cat stoves have a bypass around the catalyst for loading wood and if PE was going to put in a restriction perhaps that is what they should have done. The simpler approach is to gradually remove the restriction by modifying the flame shield until the point is reached where smoke doesn't spill into the room with an active fire. I don't overload my stove and generally re-load every 45 minutes to an hour on cold days, so the door gets opened frequently. My one mod with a deflector will stay in place as it is helping and not hindering in any way. BTW, In 30 years of operating our Regency stove, we never had this issue. Derf
 
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Here are pictures of the air diverter/flame deflector that I installed which has helped mitigate the smoke issue. It is made from 1/8" flat bar, 3 inches wide and 18.5" long. The angle is somewhat obtuse so that when the door is opened, air is forced along the deflector downwards and inwards thus driving the flame upwards, somewhat mimicking the action of the airwash (which is ineffective once the door is opened). The deflector then traps flame and smoke, diverting it upwards around the baffle. Dual duty if you will. I installed it with 3, 1/4' carriage bolts. It does not change the way the stove behaves once the door is closed. Derf

Air diverter and smoke deflector in raw form for Alderlea T6 by Derf Summerfreeze.jpg Air diverter and smoke deflector for Alderlea T6 by Derf Summerfreeze.jpg
 
Why is the stove door being opened with a very active fire? There are many stoves that will spill some smoke at that stage including the older T6.

You'll want to watch the strong draft. Too much draft can reduce burn time and can be damaging if the stove overheats.
 
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Why? Why not? Do you let your fire die down and then start over again as a matter of practice? I heat with wood primarily and I like to keep my stove and flue temperature relatively constant throughout the day. That requires feeding it often. Like I mentioned, our old Regency didn't have this problem and nor should this new PE. So, the older T6 spills some smoke under this condition too? Interesting but not insurmountable with a few tweaks IMO. It's just a stove after all. Draught is easily controlled in an airtight stove without a stove pipe damper. Some restriction is acceptable and even desired, but my stove has too much built in with the new style flame shield. I like this stove in many ways but it has its drawbacks and PE could have addressed them. I had a close look at a 20 year old PE and it was built the same as mine and the owner's house smelled of smoke when I walked in but admittedly his chimney is considerably shorter. I'm going to put up with the smoke this winter but by next winter the smoke while reloading hot issue will be solved completely.( I hope!) Derf
 
Do you let your fire die down and then start over again as a matter of practice?
Yes, generally. Some stoves recommend this in their manuals.

Draught is easily controlled in an airtight stove without a stove pipe damper.
How are you doing this? The stove is not airtight.

Interesting but not insurmountable with a few tweaks IMO. It's just a stove after all
True, until its warranty is voided by modifying the stove.
 
Yes, generally. Some stoves recommend this in their manuals.


How are you doing this? The stove is not airtight.


True, until its warranty is voided by modifying the stove.
The PE Alderlea is an airtight stove. The only exception is the boost air which plugs from ash within a week and isn't worth discussing, and the secondary air supply which is not user controlled and does open on high draught, but it can't provide enough air to promote a runaway condition. However, the main air supply is user controlled and can be cut off completely by moving the air control lever fully to the right. On my stove it cuts the flow completely. As for warranties, they usually aren't worth the paper they're written on IMO. This will be the last stove I will likely ever buy now that I'm well north of 60, so if it needs modifying, it will be modified. I paid good money to do whatever the heck I want to it:)
 
It is far from airtight. It has unregulated boost air, partially regulated secondary air, and with the primary air control fully closed, there will still be about 10-15% air admitted. The attitude toward warranties is unwarranted and incorrect, but one is entitled to one's own opinion.
 
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"and with the primary air control fully closed, there will still be about 10-15% air admitted".

Not on my 2022 model. When the gate slides over the inlet hole for the primary air, it closes it completely. Perhaps 1% leakage but no more. Have a look next time you remove the ash pan on a newer T6. The boost air hole if functioning, is about 1/2 inch and not enough to cause a runaway condition either. BTW, by definition an airtight stove is one that isn't full of holes that need to be cemented up to prevent leaks. Those old stoves definitely needed a stove pipe damper. The fully enclosed (other than the door) nature of a welded steel stove makes it by definition, airtight. Air controls and whether they are controlled or uncontrolled are separate from that conversation. Derf
 
My 2022 PE Vista is also not airtight. Even with air control closed it lets in some air. Also when my stove backdrafted because of a cold start with a cold flue the smoke came out of joints and it still smoked up my room. 100% airtight would not allow smoke backdrafting in my room.
 
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Theses are not the airtight stoves of the 70’s/80’s.
 
"and with the primary air control fully closed, there will still be about 10-15% air admitted".

Not on my 2022 model. When the gate slides over the inlet hole for the primary air, it closes it completely. Perhaps 1% leakage but no more. Have a look next time you remove the ash pan on a newer T6. The boost air hole if functioning, is about 1/2 inch and not enough to cause a runaway condition either. BTW, by definition an airtight stove is one that isn't full of holes that need to be cemented up to prevent leaks. Those old stoves definitely needed a stove pipe damper. The fully enclosed (other than the door) nature of a welded steel stove makes it by definition, airtight. Air controls and whether they are controlled or uncontrolled are separate from that conversation. Derf
The last I checked, there is a primary air bypass hole on the newer Summit and Alderlea next to the new style air control. It's about 8mm. This is separate from the centrally located boost air hole.

How is the strong draft being regulated?
 
My 2022 T6 has a fixed hole about 1/2" diameter into the front which I presume is boost air. The holes in the removable plate plugged with ash very quickly so not much of a boost function unless cleaned daily. The main air control next to it can open and close completely. The secondary air EBT allows air in through 4 small fixed holes and the ebt flapper dependent on stove vacuum. There are no other air inlets. How do I control the draught? I do not regulate the draught. The draught is a function of stove temperature, outside air temperature, wind, and the height of the chimney. I control the air flow into the stove, not the draught directly. To control or regulate the draught a barometric damper would need to be installed or another adjustable air inlet into the chimney. Derf

"The last I checked, there is a primary air bypass hole on the newer Summit and Alderlea next to the new style air control. It's about 8mm. This is separate from the centrally located boost air hole.
How is the strong draft being regulated?"
 
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Theses are not the airtight stoves of the 70’s/80’s.
You are right. These are modern airtight stoves. Any air inlet designed into the stove whether it be fixed or adjustable has nothing to do with whether the stove is considered an airtight stove. The term comes from the type of construction that allows the stove to be airtight, Derf
 
Another observation as to why the PE stoves emit some smoke when the door is opened with an active fire even with plenty of vacuum is the available volume above the baffle plate. Looking at cutaway drawings of most major stove companies show that above the baffle they have easily 4 times the volume that PE has above the baffle. This extra volume in the upper chamber will behave like a vacuum reservoir which will effectively help to draw excess smoke (which has a higher pressure due to the increased burn rate once the door is opened) into the upper chamber toward the flue. If PE were to make their stoves 1.5 inches taller above the baffle for more free space in that area it would likely solve a lot of problem IMO. So, I'm going to cut the top off my Alderlea T6 and weld on an extension to raise the top of the stove by 1.5 inches and then weld the top back on. It shouldn't take long to complete with my welder and some scrap steel. Just kidding. Derf
 
I don’t get any smoke coming in my room when my Vistas door is opened. No issues with my stove.
 
When I open my stove I open the air fully and crack the door then open. I also have a shorter chimney. My class A is about 23’ with 2x 30 degree offsets and a 90 T connector. Still drafts very well.
 
When I open my stove I open the air fully and crack the door then open. I also have a shorter chimney. My class A is about 23’ with 2x 30 degree offsets and a 90 T connector. Still drafts very well.

I wouldn't consider 23' a short chimney.
 
I wouldn't consider 23' a short chimney.
I was saying it is short compared to the 36’ OP’s chimney. I know it is not short.
 
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I believe my stove was made either in early 2022 or 2021. Not sure on baffle since the Vista is a much smaller stove than a T6.
 
I believe my stove was made either in early 2022 or 2021. Not sure on baffle since the Vista is a much smaller stove than a T6.
Quite a bit different stove based on the owner's manual from PE. Reburn tubes rather than an expensive baffle plate. The flame shield looks completely different too and I can't tell by the drawing whether it is also a restrictor, Perhaps with the smaller fire box they didn't feel the need for as much restriction. I'm guessing on the large fire box that they wanted to slow things down to get all the unburnt gasses to circulate more so they would eventually flow by a secondary air hole and burn before going up and around the baffle. In a smaller firebox the likelihood of those gasses passing by a secondary air hole should be greater, therefore less restriction. As a guess anyway. Derf
 
My baffle is the same as in the T4. Kit is about $300 to replace it. Kit includes baffle, side rail insulation and baffle gasket. The Vista uses a combination, stainless steel baffle and stainless steel tubes.
 
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