What is used to prevent Thermix from going past the Liner T Body in the Thimble?

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mdeconinck

Member
Jun 1, 2019
9
Jamaica , Vermont
I am planning to use Thermix to insulate a 6-inch liner and do not know how to stop the Thermix above the T-Body. The Flue size is about 9 X 13. I have heard about a "block out" plate that could serve this purpose but was not sure how it is made. Thanks for any guidance or suggestions.
 
I am planning to use Thermix to insulate a 6-inch liner and do not know how to stop the Thermix above the T-Body. The Flue size is about 9 X 13. I have heard about a "block out" plate that could serve this purpose but was not sure how it is made. Thanks for any guidance or suggestions.
Why do you need to stop it above the tee body? Why not just stuff ceramic wool around the snout?

And how are you going to maintain the 1" of required thermix?
 
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Why do you need to stop it above the tee body? Why not just stuff ceramic wool around the snout?

And how are you going to maintain the 1" of required thermix?
Thanks bholler for your help and quick response. The ceramic wool is a great idea. I was just concerned about the Thermix spilling into the snout area.

I am not sure that I understand your question regarding how I was going to maintain the 1” of required thermix.

Thanks again.
 
Thanks bholler for your help and quick response. The ceramic wool is a great idea. I was just concerned about the Thermix spilling into the snout area.

I am not sure that I understand your question regarding how I was going to maintain the 1” of required thermix.

Thanks again.
Are you saying you are concerned about it leaking through the joint between the snout and tee body? As long as the snout fits properly that should not be an issue.

The question about 1" is about the insulation requirements. If this is for a solid fuel burner you need a minimum of 1" of thermix surrounding the liner to meet safety code.
 
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Are you saying you are concerned about it leaking through the joint between the snout and tee body? As long as the snout fits properly that should not be an issue.

The question about 1" is about the insulation requirements. If this is for a solid fuel burner you need a minimum of 1" of thermix surrounding the liner to meet safety code.
Thanks bholler - just was not sure if it was ok for the thermix to surround the tee body.

The flue tiles need to removed because of an offset in the exterior 27’ concrete block chimney. I should have about a 9 x 13 opening for the 6” liner and thermix. Should I use several centering rings as shown in the attached picture to help with the 1” clearance requirement?

BTW - the appliance is a Buderus oil boiler in the basement.

Again - appreciate your help.

28951639-1274-4C37-B7E4-404A713BB21A.png
 
Thanks bholler - just was not sure if it was ok for the thermix to surround the tee body.

The flue tiles need to removed because of an offset in the exterior 27’ concrete block chimney. I should have about a 9 x 13 opening for the 6” liner and thermix. Should I use several centering rings as shown in the attached picture to help with the 1” clearance requirement?

BTW - the appliance is a Buderus oil boiler in the basement.

Again - appreciate your help.

View attachment 282429
For oil I wouldn't worry to much about the clearance insulation isn't required for liquid fuels but it is still a good idea to reduce condensation. That is the main place we use thermix now
 
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For oil I wouldn't worry to much about the clearance insulation isn't required for liquid fuels but it is still a good idea to reduce condensation. That is the main place we use thermix now
Ok - great. Thank you bholler! Just trying to make sure I was following best practices and doing the right thing on my own. All your help is greatly appreciated.
 
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For oil I wouldn't worry to much about the clearance insulation isn't required for liquid fuels but it is still a good idea to reduce condensation. That is the main place we use thermix now

Good morning bholler - Thanks again for your advice. I am planning to pour in the Thermix this weekend around my liner. I just wanted to double check with you that the Thermix can completely cover the Tee Body and that I should wrap ceramic insulation around the snout to keep the Thermix from entering the wall opening. Thanks again

IMG_2644.jpg
 
Good morning bholler - Thanks again for your advice. I am planning to pour in the Thermix this weekend around my liner. I just wanted to double check with you that the Thermix can completely cover the Tee Body and that I should wrap ceramic insulation around the snout to keep the Thermix from entering the wall opening. Thanks again

View attachment 282928
Yes that is right
 
Yes that is right
Hi bholler - I am sorry to have to ask for your advice again. I was able to get the first 40 lb bag of Thermix down around the liner and some of it did make it to the thimble. I just started pouring the 2nd 40lb bag, and it looks like I have a blockage above the offset - about 4 feet below the top of the flue tile. I did not have to remove the 8x12 flue tiles, so the space is tight with a 6 inch liner.

At this point, I am inclined to give up on the Thermix - or perhaps pour it to where it is about 6 inches short of the top of the flue. It is an oil burner with a 27 foot chimney, so perhaps there would still be some benefit of having the thermix at the very top of the chimney - the last 5 feet.

The Thermix may now be bridge to far for me - and I would to just like to focus on getting the new boiler installed.

Thanks for any suggestions and appreciate your help.
 
Hi bholler - I am sorry to have to ask for your advice again. I was able to get the first 40 lb bag of Thermix down around the liner and some of it did make it to the thimble. I just started pouring the 2nd 40lb bag, and it looks like I have a blockage above the offset - about 4 feet below the top of the flue tile. I did not have to remove the 8x12 flue tiles, so the space is tight with a 6 inch liner.

At this point, I am inclined to give up on the Thermix - or perhaps pour it to where it is about 6 inches short of the top of the flue. It is an oil burner with a 27 foot chimney, so perhaps there would still be some benefit of having the thermix at the very top of the chimney - the last 5 feet.

The Thermix may now be bridge to far for me - and I would to just like to focus on getting the new boiler installed.

Thanks for any suggestions and appreciate your help.
Are you vibrating the liner? How wet is your mix? How much are you dumping at once
 
Are you vibrating the liner? How wet is your mix? How much are you dumping at once
The mix was like potting soil - lumpy and slightly moist. I was vibrating the line after every two or three scoops. The scoops were about size of a coffee can. The offset is about 7 feet from the top of the liner - and I did not notice that the Thermix had stopped going down until a few feet above the offset.
 
The mix was like potting soil - lumpy and slightly moist. I was vibrating the line after every two or three scoops. The scoops were about size of a coffee can. The offset is about 7 feet from the top of the liner - and I did not notice that the Thermix had stopped going down until a few feet above the offset.
Probably could have been a bit dryer but at this point there isn't much you can do