Stove Installations

hetas installer

I will visit your house and survey your chimney and advise you on various options available to you with our extensive construction knowledge we can provide solutions to just about any problem.

One stove may look like another stove, one chimney may look like another chimney but NO 2 installations are the same,some of the variables may include fireplace op size and type, chimney height and construction, house location sheltered or exposed, insert or freestanding, top or rear outlet, 5" or 6" outlet, dry or wet stove, stove size and manufacture but to mention a few. All these variables need to be considered before and during installation.

Choosing a Stove

When choosing a stove it is important to select one that suits your requirements and not flavour of the month. A major consideration is sizing it correctly, too small and not enough heat, but too big it is not operated at its optimum level and being closed up and therefor only slumber burning. Boiler stoves while providing heat to the whole house, must be connected in correctly and this can be technicially difficult if no provision was made when initial heating system was being installed. Select a stove that suits your circumstances and lifestyle.

Modern Stoves

Modern stoves operate at a much higher temperature then older stoves of similar size. Due to the high temperatures in the firebox a lot more heat to the room is in the form of radiant heat. This is achieved by way of using features such as the shape of the firebox, surrounding the firebox with insulating materials that reflect the heat back out and controlling airflow from entry to exit, thereby getting the oxygen to react with the fuel to have complete combustion of the fuel supplied, extracting as much of the contained energy in the fuel as possible.

Air Intake

Stoves may have up to 3 seperate air in takes.

Primary Air- is supplied through the grate under the fuel stock and would have being the traditional air supply in the stove. It is especially useful for getting the fire started and adjusted to maintain the fire.

Glass Wash Air- clean air that flows down in front of the glass to help keep it clean and supply air to maintain the fire.

Tertiary/Clean Burn Air- is supplied through the underneath of the stove and flows up along the back wall of the firebox being heated in the process, before being fed in above the fire to give an afterburn. This only starts to work when the temperature inside the firebox has reached 350C. This burns off unburnt hydrocarbons rising in the smoke from the main body of the fire in a similar way that a turbo operates in a car, extracting more energy from the fuel and reducing pollutions in the smoke being emitted from the chimney. The pollutions in the smoke is so reduced that they can be used in cities like London. This cannot be adjusted but is designed in such a way that the more fire there is in the stove the more air is drawn into it. How the air supplies are designed into the stove and operated by the owner will make for a successful functioning stove.

Stove Construction

The stove body is constructed using one of two methods:

Individual cast iron sections are bolted together with high temperature sealant used to seal the the joints. This was how stoves were traditionally assemibled and gives more traditional appearance.
Steel plate which can be bent and welded together and gives a more contempoary appearance.

While different parties portray one system to be better than the other, in my experience it is dependent on the manufactures of the different systems and prioritising attention to detail and how much they have prepared to invest in fine tuning the output and durability of the unit, while final price does affect the quality it is not always directly proportional.

Fuels

Choice of fuel has an major effect an heat output, and maintenance of stove and chimney, while a multi fuel stove can burn any fuel, one fuel maybe better suited to a particulat stove then another. While advice maybe given beforehand the owner should try out different fuels to find out what functions best after installation. One thing common to all fuels it that they must be completely dry.

Fuels that contain moistures are going to require heat to reduce water content enough to allow them to burn. This means that heat is being absorbed from the fire to raise the temperature of the moisture contained within the fuel enough to convert it to water vapour. This water vapour latent smoke is not as hot as it should be, and cools back down much quicker as it rises up the chimney, forming deposits on the side of the chimney as creosote.

Chimneys

Chimneys play a major part in a good functioning stove. The height difference is the first thing to be considered as the air pressure difference between the bottom and top provides a natural up-draught, the more the height difference is, the greater the air pressure difference is, the better the up-draught is, so it goes if all things were equal! factors that may affect this are, is chimney overshadowed by buildings, trees or hills, strong winds or winds from a particular direction or a cold chimney but to mention a few.

Another requirement of a chimney is to insulate. The heat contained in the smoke should not be allowed to dissipate out through the chimney structure. The surface nearest the smoke should be an insulating material thereby heating up quickly when a fire is started to provide an up-draught and not conduct the heat away into the chimney structure. The chimney should be so designed so as to withstand big temperature difference without any negative effects.

An existing chimney may require a flexi-liner be fitted, reasons for this:
Improve up-draught- the material used is very thin and heats up very quickly, the now heated liner does not cool the rising smoke and thereby assists the smoke to rise.
Maintain- liners if they have minor damage as in cracks, a liner and filling with vermiculite will prevent it from getting any worse.
Protect- the clay chimney liner and structure from the intense heat produced as the stove gets up to temperature.

Chimney Cleaning

Chimney cleaning is a very important part maintaining a well functioning stove. A chimney should be cleaned relative to the amount of use, with some requiring cleaning more often than others, reasons for this are outlined below.

Type of stove- older stoves and some new stoves don't have a secondary burn/clean burn system so the smoke contains more unburnt particles which are deposited on the flue wall as the smoke rises and cools.
Type of fuel used- some fuels are cleaner than others, timber generally being the cleanest.
Wet fuel- wet timber or turf not only gives off lest heat but gives off a lot more smoke which is deposted as creosote on the flue wall and this can be very hard to remove.
Type of chimney- traditionally built chimneys normally cause greater soot to be deposited on the clay flue walls especially if chimney is located on a outsid wall as they are harder to heat up.
Type of installation- some older installations have tight bends if rear outlet is used which can become blocked very quickly if soot falls down them, and these should be inspected more regular.
Slumber burning- letting the stove run with just the minimum fire also means the small amount of smoke leaving the stove is not very hot and cools very quickly as it rises and unburnt particles are deposited on the flue wall.

If any of the above is common to your installation, than a little bit more attention should be paid to keeping your chimney clean. The consequences of not maintaining a clean chimney range from a stove not performing to its potential, chimney fire and carbon monoxide build-up in the room.

Creosote

This is a type of soot that builds up in the chimney and should be avoided, it comes in different forms, but the one of most concern is a sticky hard glossly buildup that is very hard to remove. When conditions are right it can go on fire, and burns at a very high temperature causing clay flue liners to crack,if it becomes damp can fall off in lumps and if there are bends, block the chimney very quickly at this point.

The causes of creosote buildup maybe one or a combination of the following

Unseasoned / wet firewood or turf.
Slumber burning.
Cold chimney- external chimney.
Boiler stoves.
Chimney that is closed up over the summer can cause harmless soot with the addition of condensation to form into a damp creosote which sometimes falls down the chimney when a fire is lit as it hardens.

Some of the stoves and fireplaces fitted by our qualified stove fitters