New Princess 29 Insert - Questions - Running Very Hot & Installation

[fallingpines]

New member here, just got a BK Princess 29 Insert on Tuesday. This one replaced a 93? Country Comfort 350cc left by the previous owner. I think the final measurement of the chimney was 25.2 from base of hearth to the top of the original liner, final ss liner was around 22.5 after an elbow was used.

I started slow with firing it up to do a little breaking in and on Wednesday decided to load it up with 4 pieces of oak and activate the cat after it got warmed up. Things went well, but then it started to blow past the active range on the temp probe, even after I turned the thermostat down. I've seen the other posts where it is mentioned, I've had a similar issue with it going past the white zone on the probe and around to the 6 o'clock position. I turned it down to low and things recovered, but it stays in the top 3/4 of the active zone. I then turned it up to the 3rd dot and it again went past the active zone, but managed to stay at the edge of the active zone just over the 2nd dot. I did all of this slowly to let it settle out and avoid rapid changes. I also avoided throwing the bypass to vent the heat as I didn't want to warp the plate or crack the cat.

Contacted my installer and he came back out to seal up the elbow and connection to the new flue liner. So I started again tonight after doing a cure on the furnace cement and ran into similar issues, though not as bad, above the 4th dot it seems to climb above the active zone. I know the probe isn't great for actual temps past the "you can activate the cat now", but it remains concerning with how it wants to run past the active zone. One thing I did notice was the bypass lever needed to be pressed down very hard, more than the installer indicated when running through operation. I think that was part of the problem on the first attempt. It has now made a distinct "click" where before it went from "easy to move" to "clear resistance" and then "easy to move" again, where I thought it was properly seated. Flames were in the back and my glass got very dirty. Now that I pushed it down really hard to where it clicked, flames are all around the sides and back like my old unit. Also the cat isn't burning nearly as bright nonstop, so I'm less concerned overall, but it still seems odd it gets so hot on the low settings. What are people normally running the thermostat at? I know it's not freezing temps, so I'm testing it out in the 40s and 50s here (F).

One final question for installation, unfortunately I don't have a picture right now. My installer cemented the "flue trim ring" (mentioned in another thread) about an inch above the actual stove onto the elbow stating that it is only used for keeping debris from falling into the unit. Is that right...? The installation instructions don't really cover it as I've tried to find a proper install picture. From lurking on the forums it seems to me that the flue trim ring actually stops the air from escaping when the blower is on so that it is directed to the front of the unit. The reason it is a separate piece is so it can be properly sealed to the unit and then tightened to the elbow or liner once in place. If someone has a properly installed picture, that might help. I don't want to overstep the expert and fix it myself, so I'd need to convince him. (also installation warranty...I don't want to do any modifications on my own until the unit is properly working and tested)

I'm really looking forward to having this unit working as it should. Even with the issues, it stayed in the active zone for 12+ hours with a half load which is many times more than my older country comfort. Maybe one day I'll even get the final pieces of trim that the factory didn't include and a non dented shroud top. I already love the stove, I'd just like to get through these initial installation pains so I can really enjoy it.

 

[stoveliker]

The cat gets hot when it eats a lot of fuel. At low settings the fuel is not consumed by flames but by that cat. Decreasing the Tstat this can increase the cat temp.

Also, new cats are hyper active the first cord or so. That's normal.

The bypass so supposed to click (cam over).

And what setting on the Tstat you should use depends on how warm you want it to be. No wrong setting there...

 

[fallingpines]

The cat gets hot when it eats a lot of fuel. At low settings the fuel is not consumed by flames but by that cat. Decreasing the Tstat this can increase the cat temp.

Also, new cats are hyper active the first cord or so. That's normal.

The bypass so supposed to click (cam over).

And what setting on the Tstat you should use depends on how warm you want it to be. No wrong setting there...

Thank you for the quick reply. I'm still playing with things, but opening and then fully re-seating the bypass and pressing down to that click seems to have really stabilized things. I don't think the installer is as familiar with these inserts as opposed to the standing models. I also believe I was feeling the teardrop shape of the wire guide/pulley but not the actual cam latch. I've had it burning on high for 40 minutes now and it seems to be staying in the active zone with a surface temp of just over 500 above the cat.

I was also not fully trusting of the bimetal coil to fully close the damper when it was set so high, so being overly cautious and seeing that red hot cat had me very concerned. Rightfully so at first with the bypass not being fully locked down for a proper seal. That little bit of airflow sneaking past the bypass seems to have kept the coil from registering the heat properly and slowing things down.

This is all new and super fancy in terms of wood stoves for me. I'm used fighting the dampers on the sides of that old country comfort to keep it somewhere between red hot and going out.

Next up is getting that blower airflow sorted out. Hopefully someone can provide a picture of a proper install to show the installer. I think I'm losing heat to the chimney as the blower feels really weak and I can feel hot air coming from behind the shroud along the edges.

Update: waited a bit and tossed in another log to see if the issue had been resolved. Kept things on high. After 25 minutes the probe passed active and jumped to the 6 o'clock position. Blower fan was off to get accurate reading. Surface thermometer indicated over 700, infared thermometer indicated 768 right in front of the probe thermometer. Things got a bit smokey with what I'm hoping was additional curing of the paint...

 

[fallingpines]

Additional new question here, I was watching a few videos and came across the bypass cable change. The thermostat pictured in the video has a clean high-low adjustment sticker with a small hole. My sticker was torn in the center and the knob flops all over the place during adjustment, it doesn't stay centered. Is this normal for the new models? Opening for the side panels is much larger than the connecting rod that goes through it?

 

[stoveliker]

Do you have a block off plate installed? (Preventing heat from going up the chimney outside of the liner?)

I don't have an insert so I can't help with the details of the other questions.

 

[Ashful]

Someone with that insert (there are several here) will be along soon enough to answer the questions about knob and cable, if not then @BKVP. Welcome to the BK club. Time will tell if you earn admittance to the "BK fanboy club".

25 ft. is a tall pipe. My BK Ashford 30.1 spec'd a maximum draft of 0.06" WC, which would usually be exceeded by any pipe as tall as yours. My 30 foot pipe was actually pulling around 0.21" WC! The stove ran just fine on the taller pipe / stronger draft, absolutely no issues with control, but there were a few items you'll want to watch:

1. Startups were definitely more exciting. I'd have a ripping white-hot fire, way before the cat probe or chimney probe indicated it was time to close the bypass. This can be managed by playing your air inlet thermostat down a bit, to keep things in check, while warming up from a cold start. The message here is, "just watch it carefully".

2. I had some issues with fly ash clogging the Steelcat, if I'd run extended periods on the highest setting. I postulated that this is due to the very strong draft stirring up a lot more fly ash, than a chimney which is inside the proper 0.06" WC spec. I believe the "30" box stoves (Ashford, Chinook, Sirocco) have a more aggressive air wash than the Princess, hence them being known for cleaner glass, and this was likely a contributor. The issue was resolved (initially) by pulling and vacuuming my cat once or twice per season, and then finally by getting my draft under control. I also swapped to a ceramic cat at some point in-between, which is less prone to clogging.

3. The efficiency wasn't as good as it is with proper draft. This could be partly my imagination, I have no real data to prove it, but it does seem I am sucking less make-up air thru every door and window seal in my house, to send up that chimney, now that I have my draft under control.

So, I mentioned a few times getting my draft under control. In my case, that meant a key damper on the pipe above the stove. I open it wide for cold starts, and close it after the chimney warms up and starts sucking hard. One more thing to remember and fiddle, but truly not a big deal. I believe some insert owners have managed to rig a key damper with a long shaft on the handle, @bholler probably has some good advice on this, but I'd truly not bother for your first season with the stove. It will run fine with the too-strong draft, just watch those items above.

I do suspect that your nuclear cat was a combination of three factors:

1. It's new, and new cats tend to be super-reactive.
2. You didn't have the bypass closed tight
3. That tall chimney with (likely) very strong draft exacerbated the leaky/loose bypass damper issue

One final piece of advice, go to your favorite stove store or woodmanspartsplus.com, and order yourself 10 feet of 2" x 1/16" interam gasket. This way, you'll be ready to rock and roll if and when you ever need to remove that combustor for cleaning or inspection. Mine takes about 30 inches, so you'll get 4 changes (maybe as much as 4 years!) use out of a 10 foot roll of the stuff.

 

[fallingpines]

Do you have a block off plate installed? (Preventing heat from going up the chimney outside of the liner?)

I don't have an insert so I can't help with the details of the other questions.

No block off plate installed. I had the unit running for 2 hours on high with no issues and it was not over-drafting. I'm thinking there were issues that occurred when the installer used a sling to carry it in and might have damaged the thermostat. I've noticed that the play in the the dial directly moves the damper and can offset it.

 

[fallingpines]

Finally able to get a few photos, hopefully I can get @BKVP to weigh in on a few of these things so I can communicate any issues to the installer.

One is a (poor) borescope picture of the elbow connection with what I think is referred to as the "flue trim ring" floating above the body of the stove, it is not sealed to the body or even touching it. So I think my weak blower may be attributed to that. I was told it was only there to keep debris from falling into the unit, but sitting up like that would not affect the function of the stove. (since I specifically asked about it)

The second is the thermostat knob removed after loosening the set screw of the thermostat/damper control. I think there was a flap of foil hanging out during the install which was removed, but from other pictures and videos that I've seen, perhaps it was damaged and now allows a great deal of play in the actual adjustment and control of the flapper. Really need advice here because I can move it around enough to open/close the flapper due to it being crooked with the spring tension.

The last concern I can't get a photo of (yet) because the unit is still hot and I'm avoiding pulling it out without the installer. The bypass gasket had extra material in one corner and I'm now wondering if it can't make a proper seal when closed. I'm now sure even a small gap could be causing some of the issues I'm seeing.

 

[fallingpines]

Someone with that insert (there are several here) will be along soon enough to answer the questions about knob and cable, if not then @BKVP. Welcome to the BK club. Time will tell if you earn admittance to the "BK fanboy club".

25 ft. is a tall pipe. My BK Ashford 30.1 spec'd a maximum draft of 0.06" WC, which would usually be exceeded by any pipe as tall as yours. My 30 foot pipe was actually pulling around 0.21" WC! The stove ran just fine on the taller pipe / stronger draft, absolutely no issues with control, but there were a few items you'll want to watch:

1. Startups were definitely more exciting. I'd have a ripping white-hot fire, way before the cat probe or chimney probe indicated it was time to close the bypass. This can be managed by playing your air inlet thermostat down a bit, to keep things in check, while warming up from a cold start. The message here is, "just watch it carefully".

2. I had some issues with fly ash clogging the Steelcat, if I'd run extended periods on the highest setting. I postulated that this is due to the very strong draft stirring up a lot more fly ash, than a chimney which is inside the proper 0.06" WC spec. I believe the "30" box stoves (Ashford, Chinook, Sirocco) have a more aggressive air wash than the Princess, hence them being known for cleaner glass, and this was likely a contributor. The issue was resolved (initially) by pulling and vacuuming my cat once or twice per season, and then finally by getting my draft under control. I also swapped to a ceramic cat at some point in-between, which is less prone to clogging.

3. The efficiency wasn't as good as it is with proper draft. This could be partly my imagination, I have no real data to prove it, but it does seem I am sucking less make-up air thru every door and window seal in my house, to send up that chimney, now that I have my draft under control.

So, I mentioned a few times getting my draft under control. In my case, that meant a key damper on the pipe above the stove. I open it wide for cold starts, and close it after the chimney warms up and starts sucking hard. One more thing to remember and fiddle, but truly not a big deal. I believe some insert owners have managed to rig a key damper with a long shaft on the handle, @bholler probably has some good advice on this, but I'd truly not bother for your first season with the stove. It will run fine with the too-strong draft, just watch those items above.

I do suspect that your nuclear cat was a combination of three factors:

1. It's new, and new cats tend to be super-reactive.
2. You didn't have the bypass closed tight
3. That tall chimney with (likely) very strong draft exacerbated the leaky/loose bypass damper issue

One final piece of advice, go to your favorite stove store or woodmanspartsplus.com, and order yourself 10 feet of 2" x 1/16" interam gasket. This way, you'll be ready to rock and roll if and when you ever need to remove that combustor for cleaning or inspection. Mine takes about 30 inches, so you'll get 4 changes (maybe as much as 4 years!) use out of a 10 foot roll of the stuff.

Thank you Ashful, great advice. I've been scouring the forums in the hopes of identifying where my problems were. The lack of a tight seal was certainly one of the contributing factors on the first day. I spent most of the night fiddling with opening and closing the bypass and adjusting the thermostat. Roughly 1/3 time something goes wrong and the temp starts rocketing up. I think the extra material up in the cut corner of the bypass is to blame, but I'm no expert. Perhaps a combination of that and the play with the damper flap.

I did have a similar experience to you with the startup time. Coming from a ceramic to the new fancy stainless it a big difference and it gets to a full gallop right out of the gate, not horrible though and my first (unsuccessful) test had the steelcat (default one?) active for around 13 hours on a half load with the loose bypass. I'm hoping once the issues are resolved it will extend that time, especially on low for an overnight burn.

I have already noticed one tiny clog of the steelcat, but not a concern yet. I actually didn't have an issue with the fly ash kicking up during the full burn, it seemed to calm down nicely after I closed that bypass and I was getting strong flames along the sides with a few washing up the front. Getting that gasket early is a great idea since it gets very hard to find during the cold season. I'm in MD so we are just leaving stove weather, but it has been chilly enough to test this new toy out at night.

 

[stoveliker]

No block off plate installed. I had the unit running for 2 hours on high with no issues and it was not over-drafting. I'm thinking there were issues that occurred when the installer used a sling to carry it in and might have damaged the thermostat. I've noticed that the play in the the dial directly moves the damper and can offset it.

The block off plate has nothing to do with overdrafting.

It is to block off the *outside* of the chimney from the insert. So that heat from the insert does not go up the chimney between your liner and the (clay tile?) chimney. It's basically to close off everything from the hearth, with the only things going up are the gases inside the liner.

If there is no block off plate, cold air is sinking down there, and you loose heat going up there. This might (I think) also affect the thermostat that would be more open because it's colder.

 

[fallingpines]

The block off plate has nothing to do with overdrafting.

It is to block off the *outside* of the chimney from the insert. So that heat from the insert does not go up the chimney between your liner and the (clay tile?) chimney. It's basically to close off everything from the hearth, with the only things going up are the gases inside the liner.

If there is no block off plate, cold air is sinking down there, and you loose heat going up there. This might (I think) also affect the thermostat that would be more open because it's colder.

Oh, very limited sleep right now. There is just the insulated ss liner that goes up to the plate closing off the top of the chimney. ''

I think that flue trim ring is supposed to keep the air being forced in from the blower from escaping around the exhaust so it makes its way to the front. So install issue right there which needs a fix if true. The old chimney had the block off plate directly above the unit about 2 feet above which opened into the ceramic. They claim the new way of doing things is not to use one if there is a solid connection all the way to the top, in my case the 22.5 or so foot insulated liner. The chimney itself is closed off completely at the top with the new cap.

 

[stoveliker]

I think the old chimney had a damper.

A plate at the top does not prevent the heat from going up and heating all that masonry.

It's not "old" to do that, it's commonly advised, and smart to add a (insulated) block off plate.

 

[BKVP]

OP,

You sent us an email last night, correct? I responded to your email.

Thanks
BKVP

 

[begreen]

Finally able to get a few photos, hopefully I can get @BKVP to weigh in on a few of these things so I can communicate any issues to the installer.

One is a (poor) borescope picture of the elbow connection with what I think is referred to as the "flue trim ring" floating above the body of the stove, it is not sealed to the body or even touching it. So I think my weak blower may be attributed to that. I was told it was only there to keep debris from falling into the unit, but sitting up like that would not affect the function of the stove. (since I specifically asked about it)

The second is the thermostat knob removed after loosening the set screw of the thermostat/damper control. I think there was a flap of foil hanging out during the install which was removed, but from other pictures and videos that I've seen, perhaps it was damaged and now allows a great deal of play in the actual adjustment and control of the flapper. Really need advice here because I can move it around enough to open/close the flapper due to it being crooked with the spring tension.

The last concern I can't get a photo of (yet) because the unit is still hot and I'm avoiding pulling it out without the installer. The bypass gasket had extra material in one corner and I'm now wondering if it can't make a proper seal when closed. I'm now sure even a small gap could be causing some of the issues I'm seeing.

View attachment 294022 View attachment 294023

Do you have a shot higher up on the elbow coming off the flue collar, where it joins the flex liner? There seems to be a liberal smearing of stove cement on these connections which most likely will not hold up over time. I'd like to see if this is a proper liner elbow with a screw clamp joining it to the liner or just a standard 6" elbow that the liner was screwed to.

 

[BKVP]

OP,

This shows the factory installed trim ring. When we build them it is tight to the top of the outer box. Then a liner can be connected to the flue collar. Often an adapter is used by the installer.

We would encourage the installer to use furnace cement right around the trim ring as it should never need to be removed and a properly connected liner would result in no issue when the chimney is swept.

It's now Friday and you joined the BK tribe just a few days ago. Go ahead and keep on burning and have no concerns. You can always reach out to us at 509-522-2730 for support or contact your dealer.

Thanks
BKVP

 

[fallingpines]

Do you have a shot higher up on the elbow coming off the flue collar, where it joins the flex liner? There seems to be a liberal smearing of stove cement on these connections which most likely will not hold up over time. I'd like to see if this is a proper liner elbow with a screw clamp joining it to the liner or just a standard 6" elbow that the liner was screwed to.

There is a screw clamp higher up, hard to get a picture without pulling the stove out and taking everything apart. I miss the easy access the country comfort had just to check on things and clean behind the insert.

 

[fallingpines]

OP,

This shows the factory installed trim ring. When we build them it is tight to the top of the outer box. Then a liner can be connected to the flue collar. Often an adapter is used by the installer.

We would encourage the installer to use furnace cement right around the trim ring as it should never need to be removed and a properly connected liner would result in no issue when the chimney is swept.

It's now Friday and you joined the BK tribe just a few days ago. Go ahead and keep on burning and have no concerns. You can always reach out to us at 509-522-2730 for support or contact your dealer.

Thanks
BKVP

View attachment 294030

Thank you for this explanation. We found somewhat of a reference in the installation manual, but it was a very different take on how that part should be used. They are more accustomed to installing the other models and this is one of the few Princess 29 Inserts they have dealt with over the years, none of the other inserts had this sort of collar or a need to seal something to the unit during install.

They should be coming by this afternoon to take another look and see what might be needed to change things around a bit for the correct seal and retain access if it is ever needed in the future and they are likely to be giving your team a call.

 

[fallingpines]

Here was one of the other items being considered for causing trouble. I know the bypass plate clamps down super tightly, but with the way it randomly decided to reach high temps, there was a thought that this could be bunching oddly during the clamp down and letting some air slip past.

 

[fallingpines]

I think the old chimney had a damper.

A plate at the top does not prevent the heat from going up and heating all that masonry.

It's not "old" to do that, it's commonly advised, and smart to add a (insulated) block off plate.

The oddest thing was, the old chimney had no damper, it just stayed open all year long and you basically had to plug the stove if you wanted to stop any backdrafting during humid days. The only way I actually had to control the burn was the two side dampers. It was a country comfort 325CC (found the once removed and re-located plate).

I mentioned the block off plate when meeting with the installers at lunch, they wrote it down to consider, but I'm not sure its a common occurrence down here along the coast with mostly mild winters.

Photo not mine, just the same design and model

 

[stoveliker]

I'm not convinced a leaking bypass would cause the cat to overheat - in fact, more of the cat fuel would disappear through the bypass rather than thru the cat, leading to lower cat temps. Imo.

 

[stoveliker]

The oddest thing was, the old chimney had no damper, it just stayed open all year long and you basically had to plug the stove if you wanted to stop any backdrafting during humid days. The only way I actually had to control the burn was the two side dampers. It was a country comfort 325CC (found the once removed and re-located plate).

I mentioned the block off plate when meeting with the installers at lunch, they wrote it down to consider, but I'm not sure its a common occurrence down here along the coast with mostly mild winters.

Photo not mine, just the same design and model

View attachment 294055

Then I don't understand the following earlier remark:
"The old chimney had the block off plate directly above the unit about 2 feet above which opened into the ceramic."

All I'm saying is that a cold air falling down the chimney is bound to open the Tstat, leading to shorter, more intense burns (and possibly heat disappearing up the flue outside of the liner). Hence a block off plate where the liner enters the chimney is a good thing to do.

 

[fallingpines]

Then I don't understand the following earlier remark:
"The old chimney had the block off plate directly above the unit about 2 feet above which opened into the ceramic."

All I'm saying is that a cold air falling down the chimney is bound to open the Tstat, leading to shorter, more intense burns (and possibly heat disappearing up the flue outside of the liner). Hence a block off plate where the liner enters the chimney is a good thing to do.

I agree, it would be beneficial in the long run to install one and limit the space being heated back there. The original damper was replaced by an "older style" block off plate with the short pipe run from the old stove to the ceramic.

No arguments that it could help things, it was just not covered by this install and not on their normal install package. I'll be going with their recommendations to begin with, especially while working through this troubleshooting. I did ask about it when speaking with them today.

 

[bholler]

The oddest thing was, the old chimney had no damper, it just stayed open all year long and you basically had to plug the stove if you wanted to stop any backdrafting during humid days. The only way I actually had to control the burn was the two side dampers. It was a country comfort 325CC (found the once removed and re-located plate).

I mentioned the block off plate when meeting with the installers at lunch, they wrote it down to consider, but I'm not sure its a common occurrence down here along the coast with mostly mild winters.

Photo not mine, just the same design and model

View attachment 294055

Block off plates are not common with stove installers at all. It is not required by code at all so they don't do it. But it really does make a big difference. The furnace cement it far from permanent it will crack and crumble away shortly

 

[fallingpines]

Just an update for anyone following along with this, thanks for all the help so far.

I spoke with the installers over lunch and as expected they were very eager to get things working correctly. We went over all the items discussed so far in the forums that any of us had seen. They were not as familiar with the newest revisions to the BK Princess inserts, but took the information that BKVP sent over along with their own info gathering to work out where there was confusion in the install.

A couple guys came over later in the afternoon to run through some ideas in an attempt to get things working properly for the weekend. We also all laughed over the fact that we thought we had engaged the lock on the bypass and didn't realize it needed that extra force to hear the solid click. They will be sure to cover that with another new owner in a few weeks during the next princess install. The trim ring was seated to what should be the proper position and is not likely to have have leaks now. They also checked all the gaskets and made a few other adjustments while we all got familiar with the unique quirks of this particular model. (as opposed to the other BK inserts)

The BK team has assured both me and the install team that in many cases the cats burn very hot while breaking in, so as long as my surface temps stay within reason, I should not have any concerns with damaging the unit. Looking forward to trying it out again and will update when there is more to share.

 

[stoveliker]

Nice to hear the installer is working well and learning with you!