Insert 7 - chimney sweep

The new stove needs a flue pipe of 18cm diameter, the existing galvanized steel pipe is 20cm. We'll insert a new inox 18 cm pipe into the 20cm existing pipe.  Before that the old pipe needs cleaning: sweeping. I guess it's never been done before. 

Bought a chimney sweeping set on a certain online store, €30, consisting of a brush, and 12 flexible rods that you can attach to eachother, to use it to clean the chimney, rotating the brush using an electric drill.

Closed the pipe off at the bottom with a very strong bag. You really don't want soot in your house. And so don't we. It's not a little, I think the bag contains about 550 g dirt.

Insert 6 - Metalfire Optimum - enclosure partly demolition

The old stove needs removing to make room for the new one. Very important: what size pipe is the chimney channel? The Metalfire needs an 18 cm diameter flue pipe, the existing channel is a 20 cm galvanized pipe. Two problems: 20 cm is too wide, and galvanized steel is not suitable as a flue pipe.

The engineer hopes there is a second tube inside this 20 cm one, that is 18 cm. 15 cm would be trouble. (15, 18 and 20 are standard sizes)

As it was...

Roasting Papaya and Tex

Take the front of the enclosure off:

Removed the old stove, there is a raised platform there, ladrillo and cement:

Also note: no insulation whatsoever.  That is bad. Walls and pillars need to be protected from a stove's heat.

Brittle cement, pebbles, and thus a hole in the floor:

The chimney flue pipe is a single 20 cm pipe, galvanized steel. Rubbish!

The good news is that there is no 15 cm channel in there, so we can just put a new 18 cm flue pipe in there, Engineer Jansen already is assembling a shopping list for 18 cm wide inox pipe materials. 

Also, the inside of the enclosure needs insulating the walls. Rockwool Firerock seems nice, semi-rigid rockwool panels 100x60x3cm. Comes in boxes of 10, for ca. €150. But more on that later.

Fill the gap in the floor with cement for an even level floor:

Leftover bits:

Oooh!

 

Insert 5 - Metalfire Optimum - arrived

In Metalfire Optimum you can read about engineer Jansen's lust for a Metalfire Optimum insert wood stove.  After much deliberation an Optimum 700 was ordered, and it has arrived. The delivery service did not have a cart to lift the pallet up 10 cm, so they could not lift it up to the porch in front of the front door, which is 10 cm above street level. So, it was left outside, next to the porch, at street level.

Grmbll. What to do.

Engineer Jansen decided to buy coaster wheels that can carry this 200 kg heavy piece of equipment, and use some steel profiles to devise sort of a cart. The wheels can carry 650 kg divided among 4.

Well, it may look easy, but it cost all day, and given the engineer's condition it was rather exhausting.

1. Move the pallet

Here it is next to the front door, street level, note the 10 cm step up:

Wheels attached, such that when the bolts are screwed into the pallet the pallet is lifted a centimeter above the ground, resting on the wheels:

Rotated 90º, in line with the front door:

Rotated 90º, in line with the front door, wheels removed:

2. Now remove the stove from the pallet:

Attach steel profiles with wheels:

The profiles are 2 cm above the wooden beams the stove is on:

Tighten these bolts and you lift the stove:

Screws!

Well, that was the theory. The stove is placed on two wooden beams, but those beams are screwed onto the pallet with 4 long screws. The points of those screws were bent, as the cart they used bent them. So, engineer Jansen could not unscrew them. Bending the screws back did not work, not enough room.  Drilling the head of the screws off did not work either, it has cost the engineer one of his drill bits. Could not saw off the ends of the screws either. 

Decided to drill holes around the screws, and force lift the beams off of the pallet, then use the iron saw to saw through the screws.  That worked.

Here the contraption stands 2 cm above the pallet after tightening the bolts:

And wheeled it off:

3. Inside!

Metalfire Optimum 700-900?

Now we have 4 m3 firewood piled up, and it's 33º and end of June, it's time to take steps for the new stove.  Engineer Jansen really likes the Metalfire Optimum inserts. There are two versions, a 70cm and a 90cm wide version. The 70cm should suffice for our heating needs, but big is beautiful, and an Optimum 900 would be...  nice. The price difference is minimal.

Find out if it would fit the existing mantle: make a hole to access the interior for measurements:

Ladrillo

The casing is made of ladrillo, ceramic blocks, 7cm thick.

Inside

Odd, no insulation anywhere. Yes, that is a concrete pillar at the back. It should have been insulated from the stove! Bad!

Measurement

The Metalfire 900 is 904mm wide, installation specification tells you to surround the stove with plates of Silca T300, 5cm thick. So, minimum width is 1004 mm. The inside of the casing is 92cm. So, an Optimum 900 does not fit.

That is disappointing! Asked Metalfire if an air gap between stove and wall of 1 cm would suffice. It won't, they say. No idea if ceramic ladrillo really cannot withstand the heat. Will find out. Else the engineer will have to accept an Optimum 700.

Insert 4 - other options

Other options. Usually stand-alone wood stoves, I like soapstone clad, for heat storage. Such wood stoves are also called "nordic", or "swedish" stoves.  These you stoke relatively small fires in, starting in the morning, gradually heating up the heavy stone structure. 200-300-500 kg of soapstone! The heat is released for hours and hours after that. Alas, these are slow stoves, while in the south of Spain the temperature during the day can be quite nice, and you don't need a stove. Only in the evening, when it gets cold you want warmth quickly. Soap stone stoves are not really suited for that. You want a metal stove that can generate heat immediately.  But, these are really beautiful!

These caught my eye in the Attika catalog. But, Attika does not make stoves themselves, they market other manufacturers stoves usually.  

A standalone woodstove would mean removing the existing insert and it’s enclosure in the living room. Quite doable. Not different from installing a new insert, as that requires breaking down part of the enclosure, too. Decisions.

Attika Coluna (fantastic!) made by Hans Greub, CH

Attika Geo (Rais - Denmark)

Heta Scan-Line 40 (Denmark)

Attika ART-10 (Hans Greub, CH)

Hans Greub Furka 2

Hans Greub Combin L

Hans Greub Combin S

Rocal insert 50V (Spain)

Heta Scan-Line 550 insert 5,3kW

Xeoos twinfire Magna (Xeoos, Germany)

The Xeoos is a novel stove, aiming for very efficient and clean burning. You light it, then switch to burning mode. Then what happens is that the burning gases do not go up into the chimney, but DOWN into the bottom compartment, where they burn. Amazing! Look at the website: Xeoos

Insert 3 - Metalfire Optimum 700

Our current old Rocal insert is not very efficient. According to a calculation engineer Jansen found on the internets, so it is true, you need to divide your room's volume in m3 by 14, to find the number of kilowatts necessary for heating. For us that is 9,2kW.  You should add 1kW for every big window, but I did not do that. We're in southern Spain you see.

I wonder if the old insert has that capacity.  I think it's intended more for a "fun" fire, not to seriously heat a room, let alone a house. The heat exchange is at the back and top of the metal box of the stove, where an airflow is maintained by a ventilator.

The rest of the heat escapes through the chimney. Looking for a more elaborate heat exchanger in an insert "Kalfire" was found, and later "Metalfire" from Belgium. Kalfire has a front glass that slides up, Metalfire has a door with a handle.

Here is the schematic for a Metalfire Optimum.   Lots of zig-zag plates that take over the heat from the hot gases:

Three versions:

The first is the plain insert, the second has a "convection mantle",  the third has a block of soapstone for heat storage and slow dissipation for hours.

Enclosure

The insert must be inserted in an enclosure,  like this:

Airflow is by convection only, there is no ventilator. The convection mantle makes installation even easier.

Interior

Interior of the fire chamber can be a combination of Skamol (vermiculite like ceramic material) and metal, and ashpan:

All metal interior

Metal bottom, skamol side and top

All skamol

The metal versions can also be colored, terracotta, gold, ...

See for yourself what versions there are:   https://www.metalfire.eu/en/products/wood-fireplaces/optimum#finishes

They even provide a 3D model, that was immediately incorporated in engineer Jansen's LiveHome3D drawing: