Will a Block Off Plate/Roxul Fix This...Help!!!!

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I dunno. Something still seems to be wrong here. If you have an initial fire, then are doing a full reload on a bed of coals, the insert should be up and cruising around 500-600* in short order something like 10-15 minutes maybe 20 tops. When I do that with my insert, I have trouble keeping the temp under control as it shoots right up to 600-700* in no time even with cutting the air all the way closed. The cats piled in front of it start to smell like Chinese food. If I left it open for 70 minutes there would be a molten pile of slag in the disintegrated chimney and some small assorted charred skeletons on the floor there. Something is amiss in this set up, either with draft, the insert or (I know, I know) the wood. I know we were working with the theory here that the flue without the block-off plate and insulation is stealing your heat and that's surely a possibility but would manifest itself more in the way of not heating your house sufficiently overall and not with the stovetop taking forever and a day to get up to a temperature.
I agree...something is not quite right. But like I've said previously, once I get the insert up to crusing temp (450 to 500) all is well! This insert kicks out really good heat into the house and my heat pump stays off. The problem seems to be getting the insert up to cruising temp within a reasonable amount of time...then keeping it at those temps before the firebox starts cooling down again. I am trying another batch of wood in preparation for the big storm tonight and over the weekend. I found another neighbor who has a ton of 3 to 4 year seasoned cord wood and was able to get a bunch from him over the last few days. I have been checking moisture content with a reader, banging them together...and most of the stuff is bone dry...right around 8 to 10%. So I hoping I might see a difference this weekend with the temps, going to start burning tonight and all weekend. I hoping some better wood and eventually a block off plate and insulation will resolve this. Of course...I'm still waiting for the dealer to get back to me on all of this? After I detailed the problem with getting up to cruising temps/ and holding them...he said he would look into and get back to me and the silence has been deafning! Thanks for the feedback...will update this post later in the weekend:)
 
Okay...really need some advice here. I have a new Hampton HI300 insert installed in September 2015. I have a Center Hall Colonial just under 2,000Sq.ft with an fairly open floor plan & center stairwell, house is very well insulated & upgraded with new high efficiency windows throughout last year (barely notice heavy wind/rain unless I look out the window). I have a 28ft exterior chimney, Pre-insulated, 6" ovalized, SS liner, but no block off plate or insulation to speak of above the insert. Here's the problem...things were just fine with the insert in the months following the install when the temps have been moderate (40 to 50's). But now that we have been getting temps below freezing lately...it is taking almost two hours to get this insert up to crusing temps (around 450 to 500 degrees). Sent this blow by blow of last night's burn to the dealer today looking for some help on what the problem could be:
  • 4:00Pm Outside temp about 23 degrees (heat pump on/house temp 70 degrees)
  • 4:35PM Started Top/down initial fire, loaded fire box with bone dry kindling and bone dry splits, air intake wide open and blower off...flames burning very hot!
  • 5:00PM Initial fire burning down to coaling phase, but Condor thermostat on the upper/middle part of door frame barely reading 200 degrees?
  • 5:10PM Raked coals forward and loaded the firebox full (N/S) with with bone dry splits, checked with a moisture reader (all <18 moisture content)...Condor still barely at 200 d.
  • 5:20PM Firebox burning really well, air intake wide open, blower still off...Condor barely reading 300 degrees (about 280).
  • 5:35PM (1 hour after starting initial fire)...firebox is full of rolling flames, burning what appears to be a hot fire...Condor now reading about 350 degrees?
  • 5:50PM Fire buring hotter, blower still off...Condor now reading about 375 degrees?
  • 6:00PM Fire burning well, I'm starting to close air intake down a little, good secondary flames burning from baffles, glass completely clear...Condor just barely at 400 degrees?
  • 6:15PM Fires is well established, good bed of coals established, very good secondy flames, air intake closed down to about half open...Condor now reading about 450 degrees?
Taking an hour and a half (sometimes 2 hours) to get the insert to crusing temp has been the norm since we have gotten into temps below freezing. I put the blower on any time BEFORE I reach 450...the firebox temp will start to drop off?? Problem is...I can't really start kicking good heat out into the living area with the blower until I get to crusing temp...which is taking the better part of two hours!!!
So...am I just losing heat to the masonry & flu without a block off plate & Roxul, etc. Or is ther something else wrong here?? Would love some feedback!
Hey guys...just following up on this thread I posted from last February. I had the dealer install a block off plate this September and I wanted to wait until we had some frigid temps this season to respond regarding how the BOP has worked. We had a string of pretty cold temps over the last 3 or 4 days and in my area of eastern PA two of those recent nights got down into the mid 20s. All I can say is thanks to everyone on this site that pushed me to get the block off plate (bholler, hogwildz, Begreen, etc.) because it is literally night & day from what I was experiencing last winter without it. Bottom line is the HI300 heats up much, much faster, burns much more efficiently and maintains firebox temperatures much, much longer. I first noticed the difference in shoulder season when I was easily getting cooked out of the family room with just small loads in the firebox. I was getting the downstairs up to 78 without even wanting it that hot and the upstairs around 74...had to build much smaller fires because of this and keep the insert fan off.

During the recent cold front when it got down into the mid 20s overnight I was able to keep the downstairs of my 2000sq ft Center Hall Colonial at 73 to 74 and the upstairs at a comfortable 70 to 71!! Last winter during the frigid temps without the block off plate it was taking me 60 to 90 minutes to get the insert up to cruising temp...and the temps would start dropping pretty quickly soon after I got it up to 500 or so. Also noticed that I can now get very long, efficient overnight burns with plenty of hot coals left over in the early morning to start a roaring fire again in a very short time.

So my conclusion is...if you have an exterior chimney don't let any dealer ever tell you a block off plate is not necessary because they are full of it. I can attest to this fact and feel like I have a whole new insert this year. Even though the HI300 is only rated to heat up to a 2000sq ft house...I can honestly say it is now heating my 2000sq ft house fairly easily:) Just want to thank you all for the guidance and give you all an update.
 
Thanks for updating. We are getting this insert and I plan to do the BOP and side and back insulation with Durock and Roxul as shown in the insulation thread I've been reading.
 
My insert install in an external chimney was done without an insulated liner and no block off plate. They did stuff some roxul at the bottom and top of chimney around the liner. Without having anything to compare it to I think I'm getting pretty good performance despite the install. However, seeing these sorts of conversations make me wonder what I'm missing out on. While at this point replacing the liner with an insulated one isn't an option for me, I'm considering installing my own block off plate and maybe insulating around the insert.

So, my question is - would just the block off plate be worth doing if there liner isn't also insulated?
 
Thanks for updating. We are getting this insert and I plan to do the BOP and side and back insulation with Durock and Roxul as shown in the insulation thread I've been reading.
Definitely the best way to go...make sure the BOP is done at the time of installation. You will absolutely get much better performance out of the insert with it! Like I said...I learned the hardy way my first season by letting the dealer tell me it wasn't necessary. Don't fall for that nonsense and good luck!
 
My insert install in an external chimney was done without an insulated liner and no block off plate. They did stuff some roxul at the bottom and top of chimney around the liner. Without having anything to compare it to I think I'm getting pretty good performance despite the install. However, seeing these sorts of conversations make me wonder what I'm missing out on. While at this point replacing the liner with an insulated one isn't an option for me, I'm considering installing my own block off plate and maybe insulating around the insert.

So, my question is - would just the block off plate be worth doing if there liner isn't also insulated?
I would think even with a non-insulated liner...a BOP would have to help. But I am no expert and would defer to the many experts who post on this site. In addition to the hearth.com staff, bholler is a professional chimney sweep who provides great guidance to newbies on this site. Also hogwildz and others. By the way...my dealer tried to tell me an insulated liner was not needed prior to my install, but thankfully I had just found hearth.com and was able to get advice from the pros on this site to insist on one. The dealer agreed to install the insulated liner with an upcharge...but I was okay with that as long as I got the insulated liner. When it came to the BOP he was completely dismissive of them and would not do it. It was only after my frustrations with the loss of heat during frigid outside temps last winter that I started e-mailing him about my ongoing frustrations! So I insisted they install one at my expense this fall and they put one in. And based on the performance of the insert this season...I'm very glad I did:)
 
In some respects I think insulating the smoke shelf etc and adding a block-off plate is even more important when you have an uninsulated liner. The first few feet of liner coming off the stove and passing through the damper and into the smoke shelf is kicking off tremendous heat. Without insulation that heat is rapidly lost to that big open space cooling the flue gases. I was measuring brick temps of 80F outside at the level of the smoke shelf.

After insulating the area, the gases stay much hotter while the plate keeps more heat in the stove. So for a given load I could cut air more, still have higher sustained stove temps and had a cleaner liner at the end of the year.
 
Thanks all. Looks like I'll be installing a block off plate...

Mellow, I have checked the temp of the bricks from the outside. It was showing 60-70 F with the outdoor temp in the 30s. So, I'm definitely losing heat. I did wonder how "bad" that was. I would think that even with the most insulated installation there would be some heat transfer to the bricks outside.
 
Correct. There will still be some heat transfer with a sheet of insulation behind the stove, but it will be less if you can put 1" of micore back there.
 
Buy an IR gun and measure the temps of the brick on the outside, that will let you know if you are losing heat to the outside. Correct me if im wrong(still a new guy) I have an BK Insert reading here somewhere I read my insert traps most of the heat inside the box then goes into the cat and heat that comes out of the cat is at a lower temperature correct? If so how does a masonry flue pipe heat up the bricks (heat sink) seems like a good selling point for me or not?

Correct me if im wrong(still a new guy) I have an BK Insert reading here somewhere I read my insert traps most of the heat inside the box then goes into the cat and heat that comes out of the cat is at a lower temperature correct? If so how does a masonry flue pipe heat up the bricks (heat sink) seems like a good selling point for me or not?
 
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Heat will migrate to the cold masonry from every part of the stove. An insulated flue liner helps reduce heat loss of the flue gases in the flue. The flue gases are cooler with a properly working cat so keeping them warm is even more important in helping reduce creosote condensation in the liner. Still there will be some heat radiated from the liner and flue collar, especially if it's not insulated all the way to the flue outlet. The insert body is another source of heat as room air is pulled in, circulated around the firebox and the heated air is sent back into the room. Keeping the heat from the insert in the fireplace and surrounding the stove body, as opposed to up the chimney helps raise the heat output from the blower. Insulating the back wall of the fireplace also helps reduce heat loss from the insert body to outdoors.
 
Correct me if im wrong(still a new guy) I have an BK Insert reading here somewhere I read my insert traps most of the heat inside the box then goes into the cat and heat that comes out of the cat is at a lower temperature correct? If so how does a masonry flue pipe heat up the bricks (heat sink) seems like a good selling point for me or not?

I have a BK insert as well, you still need to insulate your fireplace as it will still output heat to the fireplace you put it in. You need to insulate that fireplace so the heat says in it, your fans will transfer that stored heat out of the fireplace.
 
Hey guys...just following up on this thread I posted from last February. I had the dealer install a block off plate this September and I wanted to wait until we had some frigid temps this season to respond regarding how the BOP has worked. We had a string of pretty cold temps over the last 3 or 4 days and in my area of eastern PA two of those recent nights got down into the mid 20s. All I can say is thanks to everyone on this site that pushed me to get the block off plate (bholler, hogwildz, Begreen, etc.) because it is literally night & day from what I was experiencing last winter without it. Bottom line is the HI300 heats up much, much faster, burns much more efficiently and maintains firebox temperatures much, much longer. I first noticed the difference in shoulder season when I was easily getting cooked out of the family room with just small loads in the firebox. I was getting the downstairs up to 78 without even wanting it that hot and the upstairs around 74...had to build much smaller fires because of this and keep the insert fan off.

During the recent cold front when it got down into the mid 20s overnight I was able to keep the downstairs of my 2000sq ft Center Hall Colonial at 73 to 74 and the upstairs at a comfortable 70 to 71!! Last winter during the frigid temps without the block off plate it was taking me 60 to 90 minutes to get the insert up to cruising temp...and the temps would start dropping pretty quickly soon after I got it up to 500 or so. Also noticed that I can now get very long, efficient overnight burns with plenty of hot coals left over in the early morning to start a roaring fire again in a very short time.

So my conclusion is...if you have an exterior chimney don't let any dealer ever tell you a block off plate is not necessary because they are full of it. I can attest to this fact and feel like I have a whole new insert this year. Even though the HI300 is only rated to heat up to a 2000sq ft house...I can honestly say it is now heating my 2000sq ft house fairly easily:) Just want to thank you all for the guidance and give you all an update.
Thanks for the great update, I read through this whole thread with much hopeful anticipation of a successful outcome.

A few follow up questions:

Did your dealer pull the insert out and put in a one piece block-off plate?

Also, was any insulation put behind and on the sides?

Finally, how much did they charge you for doing this after the fact?

Thanks again for an entertaining and informative post about your issue. I really need to get my block off plate put in!
 
Thanks for the great update, I read through this whole thread with much hopeful anticipation of a successful outcome.

A few follow up questions:

Did your dealer pull the insert out and put in a one piece block-off plate?

Also, was any insulation put behind and on the sides?

Finally, how much did they charge you for doing this after the fact?

Thanks again for an entertaining and informative post about your issue. I really need to get my block off plate put in!
Yes...they pulled it and an installed a one piece
No, they did not put any insulation board behind or on the sides...but they did adhere an insulation blanket on top of the BOP
They charged me $500 bucks and I know many on the site will snicker that I got hosed...but the reality is, changing light bulbs is my limit when it comes to mechanical skills:) Plus I have a back injury that does not allow me to wrestle a 400lb insert out of the fireplace and back:) In the end...it was definitely worth the extra cost. Good luck with your install!
 
Yes...they pulled it and an installed a one piece
No, they did not put any insulation board behind or on the sides...but they did adhere an insulation blanket on top of the BOP
They charged me $500 bucks and I know many on the site will snicker that I got hosed...but the reality is, changing light bulbs is my limit when it comes to mechanical skills:) Plus I have a back injury that does not allow me to wrestle a 400lb insert out of the fireplace and back:) In the end...it was definitely worth the extra cost. Good luck with your install!
Money well spent. I'd have thought it a bit steep 13 months ago, but after installing my insert myself, including an insulated chimney liner, and wrestling with the block off plate since then (the permanent one is still just an aspiration), I now recognize the skill level involved. That, and the fact that almost every stove installer balks at installing one because it is so difficult. Don't look back, you are set up now!
 
Money well spent. I'd have thought it a bit steep 13 months ago, but after installing my insert myself, including an insulated chimney liner, and wrestling with the block off plate since then (the permanent one is still just an aspiration), I now recognize the skill level involved. That, and the fact that almost every stove installer balks at installing one because it is so difficult. Don't look back, you are set up now!
Thanks...yes, in the end spending the extra money was well worth it for me. The difference in performance & efficiency with the BOP installed is significant. I really think the dealers need to install BOPs as standard (and price it in to the total cost) for home owners with exterior chimneys. Again...good luck with everything!
 
It does take extra time and effort to put in a block-off plate, but a good dealer should recognize that this is a way to add a value-added service to their customers. It should be listed on the estimate as a suggested option with a brief explanation of the benefit.
 
It does take extra time and effort to put in a block-off plate, but a good dealer should recognize that this is a way to add a value-added service to their customers. It should be listed on the estimate as a suggested option with a brief explanation of the benefited.
Totally agree. I wonder how many dealers are on this forum? So much valuable insight and opportunity to both learn and share, as well the opportunity to connect with customers and potential customers. @BKVP is smart enough, and @bholler as well. Wish SBI had a rep like @FyreBug used to be. My apologies to those I'm missing, probably a bunch,
 
Been reading this thread with interest. I have our installer doing the install in two phases to allow me to put in a BOP. Our chimney is not external however the exterior is in the garage. Probably should still put one in?

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I would.
 
Been reading this thread with interest. I have our installer doing the install in two phases to allow me to put in a BOP. Our chimney is not external however the exterior is in the garage. Probably should still put one in?

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No downside, big upside.