Victas Fire Cement

[nicknorman]

But steel plate is also convecting heat and it's the steel where the sealant is applied. The internal stove gasses I agree are much hotter, but at the end of the day the collar where the flue goes into the stove being just 2 inches away from the water top outlet would not reach 250 degrees.

 

I'm aware of the silicone, the point about the putty is it's good for spanning large gaps, it's consistency is of stiff plasticine and can span and cope with a much larger gap that silicone, so ideal for roof collars.

 

 

Well it's not independent of the stove is it. It has to be in contact with it for it to heat.

 

 

Well sounds like a woodburner, I hardly think it's boiling at 250c though. Your central heating fluid must be boiling too I would suggest.

 

 

 

The water re enters the stove cooler, so in affect cooling it. Water left in the boiler would superheat causing steal pressure.

 

Yes the heat is being conducted (not really convecting in this context) by the steel, but if you consider that for the purposes of your point it has to flow along a relatively thin section of steel - ie there is a big difference in conduction from inside to outside the stove through a thin layer of steel, vs the amount of heat that flows "sideways" along a relatively thin steel sheet And dont forget that the boiler is not in intimate thermal contact with the stove structure, its just in the vicinity. Although back-boilered stoves obviously run a little cooler for a given firing rate, I don't doubt that the temperature of the collar area, especially on the side away from the boiler, can get very hot if the stove is being operated at max output.

 

It would be foolish argument to say that you never operate the stove at max output because one day, you might by accident.

 

Anyway, as usual I'm sure you wont be convinced, so the proof of the pudding would be to buy a stove thermometer for £8 or so and measure it yourself with the stove burning at max output.

[Ex- Member]

Yes the heat is being conducted (not really convecting in this context) by the steel, but if you consider that for the purposes of your point it has to flow along a relatively thin section of steel - ie there is a big difference in conduction from inside to outside the stove through a thin layer of steel, vs the amount of heat that flows "sideways" along a relatively thin steel sheet And dont forget that the boiler is not in intimate thermal contact with the stove structure, its just in the vicinity. Although back-boilered stoves obviously run a little cooler for a given firing rate, I don't doubt that the temperature of the collar area, especially on the side away from the boiler, can get very hot if the stove is being operated at max output.

 

It would be foolish argument to say that you never operate the stove at max output because one day, you might by accident.

 

Anyway, as usual I'm sure you wont be convinced, so the proof of the pudding would be to buy a stove thermometer for £8 or so and measure it yourself with the stove burning at max output.

 

Well as the putty I'm using has sufficed for 7 years and still if perfect condition by the look of it then it works for our stove. Next time I fire it up i'll take some temperatures.

 

BTW out boiler is part of the stove adjacent to the back, ive just noticed another water inlet or outlet to the right of the chimney again within 2 inches of the flue exit, I'm wondering if water/heating fluid actually runs in a cavity under the top of the stove surface which is directly below the chimney outlet. That would explain ours not excessively heating up. The safety cut off is so sensitive anyway if I forget to put the pump on as soon as the stove heats up it cuts off and the stove top plate won't boil water and the chimney exits there.

[nicknorman]

Well as the putty I'm using has sufficed for 7 years and still if perfect condition by the look of it then it works for our stove. Next time I fire it up i'll take some temperatures.

 

BTW out boiler is part of the stove adjacent to the back, ive just noticed another water inlet or outlet to the right of the chimney again within 2 inches of the flue exit, I'm wondering if water/heating fluid actually runs in a cavity under the top of the stove surface which is directly below the chimney outlet. That would explain ours not excessively heating up. The safety cut off is so sensitive anyway if I forget to put the pump on as soon as the stove heats up it cuts off and the stove top plate won't boil water and the chimney exits there.

I may have slightly lost the plot with this argument! I think you are talking about a diesel stove? In which case I can believe that the flue outlet doesn't get that hot. However, a coal stove can get much hotter.

[Ex- Member]

I may have slightly lost the plot with this argument! I think you are talking about a diesel stove? In which case I can believe that the flue outlet doesn't get that hot. However, a coal stove can get much hotter.

 

I've only been talking about diesel stoves, read the thread back.

[SamKingfisher]

I used high temp silicone, good to 1300c. Concur about lighting the first fire though, nasty fumes. And you are supposed to let it go off for 3 days per cm or something. I didn't read that bit first. Always read the label!

 

It's good stuff- still nice and flexible.