Recover heat from my stove

[tarakhammam]

Hello everyone
I have searched a lot on the net to try to understand something ...
and I arrived at the following result, for which I hope to receive criticism and / or advice, before the realization:



and in detail, with a skylight to see inside:



I have, since this summer, a stove that works not bad, my faith.
except that it heats the living room a lot and has a little more trouble for the bedrooms on the first, and that forces me to keep the door leading to the stairs open.
So, the thing is that I want to bring heat directly into the corridor (short but wide) which distributes the 4 bedrooms (2 on each side).
so I imagine dressing my stove with:
- on the sides and behind refractory bricks
- that I dress with insulation so that the heat of the bricks does not go into the living room
- on top, a refractory concrete plate made by me
- and finally the exterior coating
from the stove upstairs, I need about 6m of sheath, which I would run in its box on the ceiling.
the outlet will be flush with the floor of the 1st (corridor).
I add that an outside air intake is placed under the stove.
Ah yes ! the metal plate in front (above the stove) serves as a look on the inside of the beast, in case ...

does what I envision hold water?
do you have any ideas for improvement?
can it work by simple natural recovery, or does it need a recovery. forced with a fan?
in short, if charitable souls pass by and want to help me, I would be very, very grateful to them!

[Forhorse]

Considering the application, the refractory bricks are totally useless. Well-fired "normal" brick will be more than sufficient.
(Refractory bricks contain alumina so that they can withstand very high temperatures, 1000 ° C and above. A "normal" brick fired at around 800 ° C holds very well at 400 ° C or above)

Considering the horizontal distance to be covered, I think that we will have to consider forced circulation for the goal to be reached.
Without there will certainly be a circulation of hot air, but with a flow which is likely to be weak.

[tarakhammam]

thank you for the answer...

in fact, what interests me with bricks (and so-called refractory ones may therefore not be what I need) is:
- to concentrate the heat in the room which surrounds the stove (so that it escapes only in the recovery sheath),
- and restore the heat long after the stove has stopped

So "ordinary" clay bricks are enough?

[Ahmed]

The refractory bricks would represent a significant additional cost, while I confirm that they are of no use in the intended application.
As for the need or not for artificial ventilation, it depends on the pressure loss of your circuit (and therefore the section, length and positioning of the ducts): difficult to judge beforehand...

[Grelinette]

... Regarding the need or not for artificial ventilation, it depends on the pressure loss of your circuit (and therefore the section, length and positioning of the ducts): difficult to judge beforehand...

On the other hand, if the hot air goes to the upper rooms, it will automatically create an upward air flow! Must see ...

Anyway, the subsequent installation of ventilation, if the assembly provides space to install it, can be done easily, either to force the flow of hot air, or to optimize efficiency.

I have an insert with a blower that turns on manually or automatically as soon as the temperature of the insert is very high. As soon as the blower is on, the temperature rise in the room is very rapid. It is very comfortable and practical when you come home in the evening and the house has cooled down.

On the other hand, I also put a kind of hood above the insert, around the metal smoke duct, in order to recover the hot air and propelled it into other rooms.

A question that may also interest tarakhammam :

I hesitate to put ventilation,

- either by suction of hot air, therefore at the level of the room or rooms to be heated. It's relatively simple and allows you to choose to heat this or that room,

- or by propelling ambient air into the hood from where the conduits leave towards the rooms. To choose the rooms to be heated, it is then necessary to have duct closing systems.

Which technique: Aspiration or Propulsion of heating air?

[Rabbit]

On the other hand, if the hot air goes to the upper rooms, it will automatically create an upward air flow! Must see ...

There is another descendant, you have to think about it. So much for the tablecloth
cold air which is frankly unpleasant than allowing air
cooled to return to the stove to continue the cycle.
Take smooth ducts, avoid accordion ducts as well as
elbows too tight. A ventilation consumes a lot on
in the long term as much provide the probe (s) and allow free circulation
air heated to reduce engine power.

[tarakhammam]

first of all, thank you to all the contributors to this post!

actually, I will see once in operation if it is necessary to have forced ventilation ...

some questions remain:
- I would have a total of three elbows: does the box - say 20cmx20 or 30x20 - which runs to the ceiling (insulated walls ??) suffice for the warm air to circulate well, or does it necessarily require a path pipe (round and smooth) inside?
- for the room itself: ok for normal bricks, but do you have to insulate between the bricks and the exterior cladding, the idea being to keep the heat around the stove as well as possible, leaving no other escape than the recovery duct?
- finally, is it correct to want to close around the stove, so as to only allow the ambient air to pass from below (which would therefore "push" the hot air)?

do you have any opinions on these 3 questions (and others if you see any)?

good christmas everyone!

[Philippe Schutt]

Yes, a 20x20 box is sufficient
If your insert is fitted with bodywork insulation is not compulsory but recommended and the air which goes towards the rooms is taken in the bodywork, not around. Otherwise, insulation is mandatory.
If we can, we leave a game if only for the differences in expansion.

[tarakhammam]

thank you Philippe
but it's not an insert, it's a cast iron stove that I have.
and this question of "bodywork", what do you mean?
I can only take hot air around the stove; that's why I want to dress it in a room (on the sides, behind and above).

[Philippe Schutt]

there are 2 types of inserts or fireplaces:

simple, which require insulation:
http://www.invicta-sa.com/portail/images/stories/invicta/1_produits/Chauffage/foyers_et_inserts/foyer_628044.jpg

with bodywork or coat,
http://www.supra.fr/medias/Image/_img_dyn/img_produits/FR/med/FOYER_SUPRA_CLASSIQUE_162_C_BD_TR.png
the air is held against the hot walls and exits through holes where the ducts can be connected. Ventilating the case is sufficient.

In construction, the stoves would fall into the 2nd category, but you cannot collect the heat that ends up in the box, which must then be insulated.

Fans: it's better on the cold side, at least for motors and cables. Budget question too ...