No heat from Stove ( Jotul )

[Honda]

Maybe a silly question but does the stove have a baffle plate fitted? The only way I can think of for a raging fire to not heat a room is if the heat is going straight up the flue. The baffle plate prevents this.

[openspaceman]

3 hours ago, Stubby said:

I think you need to fit some vermiculite board , or bricks to reflect heat back into the fire box to raise the overall temp . 

I'm thinking along the same lines, that is that the combustion chamber temperature is not getting high enough and the secondary combustion flames are being quenched by the cold metal sides. The drawback would be that the stove wasn't designed for this and the heat exchange surfaces of the sides and back may not be sufficient to give out the power, so the stove would effectively be derated and the flue temperature would go up.

 

I had a Jotul 602 for 30 years and it took a long time to get up to heat and often I would notice a blue haze from the chimney, this is sooty particles forming a sol that reflects the blue part of the spectrum because of their size, they are formed when the secondary flame does not completely burn the carbon in the flame because the flame is quenched.

 

Modern stoves with refractory bricks reach and maintain a higher temperature quicker and the flames remain hot enough to burn out. In my street , where several people burn wood, it is quite unusual to see blue, or any, smoke nowadays.

[Jack0]

1 hour ago, Honda said:

Maybe a silly question but does the stove have a baffle plate fitted? The only way I can think of for a raging fire to not heat a room is if the heat is going straight up the flue. The baffle plate prevents this.

I’m not very up on all this …but yes I think so , pic of inside attached 

[scbk]

Look on the bright side, if you ever have any ladders/scaffold up to work on the flue, you could always get the slates fixed at the same time 

 

 

 

If you don't really need the heat from the stove, you could always have one of those electric effect fires

 

[Squaredy]

6 hours ago, Jack0 said:

No I had it fitted , the chimney was lined with 904l liner . Yes it’s a large draughty room 26 x 13 ft with original draughty sash windows and high ish ceilings . There is twin wall coming out of the roof because the chimney stack was removed before we bought the house . Tall 3 storey house . 

Is it possible for you to tell how much heat ends up in your loft void?  Assuming you have a loft void as it looks like the loft is converted.  What I am thinking is that the top of the original brick chimney is inside your roof void somewhere and presumably loads of heated air is coming out effectively doing a brilliant job of cooling your fire and living room!  If the register plate were fitted properly this would not be an issue of course.

[Macpherson]

54 minutes ago, scbk said:

Look on the bright side, if you ever have any ladders/scaffold up to work on the flue, you could always get the slates fixed at the same time 

 

 

Beat me to that😁

 

But to @Jack0 it's hard to tell from the pics if there is a throat plate in the stove, or if not as others have said all the heat is just vanishing straight up a 3 storey the flue which will have an impressive draw?

[john87]

I cannot see how the presence of a flue liner or not will make any difference whatsoever..

 

To fully burn "X" quantity of wood, will require "Y" quantity of air. This air can only go one place unless you want to gas yourselves and have a room full of smoke, and that is up the chimney..

 

Fully burning "X" quantity of wood will provide a set amount of heat determined by the calorific value of the wood.

 

This heat has to go somewhere. What you going to gain by having an insulated flue lining??

 

All you will do, is instead of the heat being absorbed by the brickwork of your house as the flue gas travels upwards [making the brickwork all nice and toasty] the flue gas will be much hotter when it comes out of the top and you will merely be making the sky hotter..

 

As i said, mine is more an open fire with doors, but if i shut them, the flue temperature triples, and much less heat is emitted from the fire itself [but the brickwork gets lots hotter]

 

Right above your stove you have a bend. I thought you were supposed to have a straight run of a good few feet before any bends??

 

john..

[Stubby]

My stove has a six inch SS liner fitting snugly inside a seven and a half inch clay liner so as insulated as it can get . And I get what you say but it does make a difference to how hot the stove gets and that is the bit that is in the room , the room you want to heat . Mine is also in a bit of an alcove and actually heats the whole house if you leave all the internal doors open .

[Muddy42]

15 hours ago, Jack0 said:

I’m not very up on all this …but yes I think so , pic of inside attached 

 

 

 

Sorry I can't really tell from your picture, when you look at the inside roof of the stove, a baffle plate should be sloping and almost completely block off the chimney, leaving a narrow slit of say 1.5 inches.  Highlighted green in the picture below:

 

This baffle plate reflects heat and unburn gases so they can reburn again. They can be iron, steel or vermiculite, indeed the whole of the inside of the stove can be lined with any of these materials. Vermiculite is a fibrous heatproof material that can be cut with a saw or an angle grinder. 

 

Any decent stove guy, or even a DIY-er could design and cut five pieces of vermiculite to line that stove (floor, rear wall, 2x sides (five sided with an apex for the new baffle piece to rest on) and a top baffle piece). As others have, this would properly "baffle" the gasses and raise the internal temperature of the stove.  It would cost less than £40 in materials, so surely worth trying before doing anything else more drastic?

[Canal Navvy]

I have experience of that stove having installed one and run it for a few years in another property. They came with a loose outlet and a knockout option to either fit the flue outlet out the back or through the top, definitely not an adjustable flue damper.

In my installation (listed building) rear exit was chosen to keep the original fire surround. 

 

I found it easy to light and as it was lit most days it didn't seem to take long to kick out the heat. I had noticed that when it was "on song" that it had the appearance of jets of flames coming out of the small holes in the secondary burn part of it's permanent air supply. 

 

After a few years I had the feeling that it wasn't as hot as it used to be so took the top off and looked inside expecting to find something bunged up with soot. Apart from the soot that accumulates on top of the baffle/secondary air  it was clean so I pulled the stove out and checked the secondary burn air intake on the back, also clean.

 

The disappearance of those jets of flame had me thinking that the secondary burn wasn't happening anymore and the only reason left was that too much air was getting into the stove and there was not enough negative pressure to pull a good flow of air through those two rows of little holes.

 

Changed the rope door seals and the little flames came back. 

 

My stove stood out in the room more with it's rear flue but was otherwise very similar to yours. 

 

Difficulty with stove problems is that there are so many variables 😉