Flue Roof Collar

[system 4-50]

I have bought one of those great lumps of iron that sits on the roof and has a hole in for the stove flue because everybody does. But what exactly is it to supposed to do and how does it work?

 

If it is just a seal between the flue and the roof, surely a ceramic one would be better?

[Phil Ambrose]

I have bought one of those great lumps of iron that sits on the roof and has a hole in for the stove flue because everybody does. But what exactly is it to supposed to do and how does it work?

 

If it is just a seal between the flue and the roof, surely a ceramic one would be better?

 

I've got a nice shiny S/S one and in Summer when not usyng fire the "H" flue lifts of and is replaced with a nice shiny S/S cap, so no it does not have to be a huge lump of iron.

 

Phil

 

I have bought one of those great lumps of iron that sits on the roof and has a hole in for the stove flue because everybody does. But what exactly is it to supposed to do and how does it work?

 

If it is just a seal between the flue and the roof, surely a ceramic one would be better?

 

I've got a nice shiny S/S one and in Summer when not using fire the "H" flue lifts of and is replaced with a nice shiny S/S cap, so no it does not have to be a huge lump of iron.

 

Phil

 

edited for spelling

[system 4-50]

I have bought one of those great lumps of iron that sits on the roof and has a hole in for the stove flue because everybody does. But what exactly is it to supposed to do and how does it work?

 

If it is just a seal between the flue and the roof, surely a ceramic one would be better?

 

Perhaps I could make my question clearer:

 

Is it intended to take heat away from the roof where it (the roof) is heated by the flue and radiate it away to keep the roof cooler?

 

Is it intended to take heat away from the flue and radiate it away to keep the flue cooler?

 

Is it intended to take heat away from the flue and conduct it into the roof to heat the boat via the roof?

 

Is it just to provide a thicker annulus (?) for the flue to go through, which has to be big to take the heat?

[Keeping Up]

I've always just viewed it as having two functions - neither of them related to heat transfer:

 

1. A convenient way of anchoring the top of the flue

2. Something to put the chimney on

[blodger]

Perhaps I could make my question clearer:

 

Is it intended to take heat away from the roof where it (the roof) is heated by the flue and radiate it away to keep the roof cooler?

 

Is it intended to take heat away from the flue and radiate it away to keep the flue cooler?

 

Is it intended to take heat away from the flue and conduct it into the roof to heat the boat via the roof?

 

Is it just to provide a thicker annulus (?) for the flue to go through, which has to be big to take the heat?

Since they originated with wooden working boats I would think that there mass and specific heat characteristics were helpful in dissipating heat and avoiding the charring of the roof/deck through which it was bolted. It probably still helps with steel boats. I have noticed on old Springers that a place that becomes holey is aroubd it since the heat & moisture accelerates rusting in the vicinity. I could be wrong?