Mapeflex Firestop 1200 degC High Temperature Sealant (Screwfix)?

[AndrewIC]

Is this stuff suitable for sealing the joint between the flue pipe and stove collar, for which I have hitherto used fibreglass rope and traditional fire cement? Anyone used it successfully?

 

(NB, Not the gap between the flue pipe and roof collar, for which I have used fibreglass rope and Geocel Plumba Flue Silicone to good effect)

 

Thanks

Andrew

[ditchcrawler]

Is this stuff suitable for sealing the joint between the flue pipe and stove collar, for which I have hitherto used fibreglass rope and traditional fire cement? Anyone used it successfully?

 

(NB, Not the gap between the flue pipe and roof collar, for which I have used fibreglass rope and Geocel Plumba Flue Silicone to good effect)

 

Thanks

Andrew

http://www.mapei.com/public/IT/linedocument/mapeflex_fire_stop_1200_gb.pdf looks good to me

[Tony Brooks]

Is this stuff suitable for sealing the joint between the flue pipe and stove collar, for which I have hitherto used fibreglass rope and traditional fire cement? Anyone used it successfully?

 

(NB, Not the gap between the flue pipe and roof collar, for which I have used fibreglass rope and Geocel Plumba Flue Silicone to good effect)

 

Thanks

Andrew

 

I used Plumbaflue at both ends of the pipe, been alright for years.

 

 

[dor]

Looking at the link ditchcrawler gave, you want to use the mapeflex AC-FR not the Firestop. The latter is more like fire cement as it is not flexible and is designed to withstand direct fire contact. You need a flexible filler, otherwise you are no better off than with fire cement.

 

I've used Plumaflue from Screwfix and Delta from a chandler. Both say they withstand up to 300C and I've used it between the flue and the stove collar for years.

[Mac of Cygnet]

I've used one of these high temperature (1200degC) sealants between the stove and flue for some time now, successfully. Unfortunately I can't remember which one, but I guess they have similar formulations. If so, choose carefully when you first fire the stove up, as the boat will be uninhabitable for at least half an hour (in my case at the bottom of the Wigan flight in the rain.)

[AndrewIC]

OK, thanks. I'm not convinced about the suitability of Plumba Flue for on-stove use, but I will try the other stuff. If it cracks and falls out... Well, so does fire cement!

[dor]

OK, thanks. I'm not convinced about the suitability of Plumba Flue for on-stove use, but I will try the other stuff. If it cracks and falls out... Well, so does fire cement!

But fire cement is probably cheaper!

 

Actually what I do is use the fire-resistant rope first, ramming it well down between the flue pipe and the collar, but not too thick so that the seal is gas tight but doesn't grip the pipe too tightly, allowing a little bit of movement. I then use the Plumaflue for the top five to 10 mm to make a second gas-tight seal whilst still allowing a little bit of movement; I rely on the deckhead collar to allow most of the expansion movement with the use of a bit of rope plus Plumaflue to provide most of the seal. This should allow up to 5 mm of movement without problems. I also let the flue pipe float just slightly above the bottom of the collar rather than resting it hard against it.

 

So far, no leaks and not cracked stove tops!

[Phil.]

If you want flexible then this is prob what you are looking for

 

http://www.stoves-etc.co.uk/InstallationProducts/SealantsAdhesives/OtherSealantsAdhesives/EnvirografHighTemperatureSilicone1200Degrees

 

Anything that says 300 degrees is prob not high enough

[AndrewIC]

If you want flexible then this is prob what you are looking for

http://www.stoves-etc.co.uk/InstallationProducts/SealantsAdhesives/OtherSealantsAdhesives/EnvirografHighTemperatureSilicone1200Degrees

Anything that says 300 degrees is prob not high enough

Thanks, now that looks promising

[Mac of Cygnet]

If you want flexible then this is prob what you are looking for

 

http://www.stoves-etc.co.uk/InstallationProducts/SealantsAdhesives/OtherSealantsAdhesives/EnvirografHighTemperatureSilicone1200Degrees

 

Anything that says 300 degrees is prob not high enough

 

That's the one I used! Definitely evacuate the boat when the stove is first fired up.

[nicknorman]

Yes the 1200C silicone is what to use. I did our stove to flue joint with it 3 years ago, it is still perfect. I don't remember much in the way of fumes but I think it was left for quite a long time (weeks) before we needed to light the stove.

Edited March 21, 2016 by nicknorman