www.woodstovewarehouse.co.uk

 
 Charnwood Island Gas Stove

Do you want the elegance and efficiency of a stove without the mess and work? Have you considered gas? A lot of wood burning/multi-fuel stoves now come in natural or LPG gas options, from the small Belfort by Franco Belge or the Gazco Brunel, not out of place in a cottage, to large Dovres and the Euro Heat Harmony at home in the largest baronial hall. These stoves have coal or log flame effect and are extremely difficult to tell from the real thing. They are all in the order of 70% efficient (compared to less than 20% for an open fire) and they often only require a class two chimney system, thus giving you further savings. (please see chimney design note for further explanation). If you have no chimney the Townsend I or II is a balanced flue stove and can just go through and external wall to brighten the coldest, dullest room with a glow and warmth.

To most English people who don’t go to ‘raves’, the term oil stove conjures up the image of the smelly paraffin wick type tin stoves that were the vogue in the 50’s and 60’s. Thankfully these dangerous items have been banished to the green house where the copious amount of damp they cause is appreciated. In mainland Europe though, where oil is a common source of heating, a more sophisticated form of oil stove with a flue pipe to vent the damp and fumes has been an exceedingly popular alternative to coal or wood stoves. These can be space heating, space heating and DHW or they can run a full central heating system. Why oil? Well if you are not on mains gas the only alternative for instant controllable heat is oil or Liquid Petroleum Gas (LPG). LPG is currently the most expensive fuel, bar day time electricity. So if you live in an area of frequent power cuts or if you have an expensive to run LPG boiler, then an oil stove could be the answer for you. It can provide a trouble free source of heat in your main room or hall very economically as well as looking good. There are models currently available with coal effect flames like gas fires, and electric ignition. Finally there are some very simple cheap models that with a short flue or chimney provide clean dry heat very cheaply for tack rooms, studios, work shops etc. You may be surprised at what is available!

The models recommended by COSI are from Euro Heat, Franco Belge, Godin and the British, Wood Warm and Don Burners ranges. These have a very simple vaporising burner with no moving parts, and with the exception of the Euroheat Thermical central heating boilers do not require electricity. Please ask for further details

These come in a number of different forms and at first it seem quite muddling. But one can broadly divide appliances into three categories which have different flue and ventilation requirements.

Any open fire can be converted to burn a mock coal or log gas fire. If the gas input exceeds 7 kW or if the manufacturer specifies an air vent will be required in the room. Inglenooks can be converted but care must be taken with any fire to see that it draws safely. If coal or wood smoke blows back into the room, you will smell it and open a window.

YOU CAN'T SMELL CARBON MONOXIDE.

It is not the fuel but the method of burning that is important, the flue requirements for the above are the same as a solid fuel fire.

The efficiency of a fire like this will be between 5% and 20%, i.e. they must be treated as a showpiece, not a source of heat.

Although a simple concept, the convector box increases the efficiency of an open fire by up to 800% !!!!

(this also applies to wood and solid fuel convector boxes). Neat, with clean designs these fit into a lot of standard fireplaces very easily. Unless stated otherwise, they require a chimney that is acceptable for a solid fuel appliance and a room vent will be required if the gas input is above 7 kWh.

Millions of these appliances have been sold over the last 30 years in the UK By making the efficiency very high, apart from reducing the fuel bill, the result is a small amount of flue gas at a low temperature. A cheaper chimney or chimney lining can then be used and houses built in the 60's onwards often had a small block construction vent for a gas fire exiting the roof at the ridge. Until recently the only fires that could be fitted to such a flue were the sort with the 'white fire brick in a row'. Not so any more, there is now a range of open convector box and 'converted' wood stoves that are extremely good looking and pleasant to sit round. One can even have them fitted into Victorian style surrounds, not to mention mock inglenooks etc. Please ask for details.

Finally, if you have no chimney any of the above gas appliances can be fitted to an external wall with a fan coupled with safety cut out solenoids to the gas supply. (Remember the Townsend I & II is a balanced flue or room sealed appliance and so does not require a chimney, just an external wall )

Also new technology has allowed flue less appliances with catalytic converters. These scrub the flue gases removing and carbon monoxide and as an added bonus cigarette and pet smells at the same time. These are 100% efficient but do require a small air vent into the room.

Since 1966 all class I chimneys built had to be lined as they were constructed. There are many different methods and materials and all have their uses, advantages and disadvantages.

To save money a lot of the big house builders started to leave out chimneys or where there was mains gas, just fit class II block flues in the party wall.

If you are in later situation then you are obviously restricted to a class II gas appliance, but that now means just about any 16" convector box or any gas ‘wood’ stove, so the choice is vast.

If you have no chimney then you must first decided on the type of appliance as the cost of the solution will vary widely according to your choice. In order of cost;-

1/ Balanced flue or power flue. Here you are restricted to using or being very near an outside wall.

2/ Internal ‘gas’ class II instant clip together chimney. This is cheap but un-insulated hence it can only be used internally or the combustion gasses will over cool and the chimney not draw.

3/ External ‘gas or oil’ class II flue. Similar to the gas but the 12mm air gap is insulated and the internal flue made of stainless steel. Both these type of chimney require a 25mm space around them to flammable material.

4/ Class I chimney sections or brick chimneys. The class I ‘instant’ chimney is constructed of stainless steel inner flue with 25mm of insulation and a further case of stainless steel. Obviously expensive, but it is obtainable in any size and can be used internally or externally.

WHETHER TO LINE AN EXISTING CHIMNEY ?

This is not a straightforward question, as it might seem. The British Standards state that if the chimney is ‘sound’ and draws a gas appliance can be connected to it, however that is not the end of the story. By connecting an efficient gas or oil appliance to a large unlined chimney the gases will condense as they rise up the chimney. This will saturate the brickwork causing damp patches and severe deterioration over the years as the products of combustion of all hydrocarbons are acidic.

In general we recommend;-

1/ If the chimney is all ready lined no further lining is required unless an oil stove is to be fitted.

2/ With an oil stove we prefer to line it with a 125mm stainless steel liner, back filled to try to achieve a gentle, steady draw, which this type of appliance requires.

3/ If a pre-1966 unlined chimney, we would definitely recommend lining for oil or class II gas appliances.

4/ If a pre-1966 unlined chimney, we would recommend giving serious thought to lining the chimney if a class I appliance is to be fitted, especially a wood stove or any appliance that heats water.

 

The next section of this booklet is the technical specification for various chimney systems and liners, followed by the prices (correct at the time of going to press) of nearly all the range we stock and supply. If you have any doubts or require help designing and matching a chimney system to an appliance, we at COSI try to offer a free custom design service. We can then supply the full system as a palletised kit from the appliance to the chimney pot which you know will work.

Eur.Ing. Graham Thornhill B.Sc. C.Eng.

Pricing

If you have been offered a price, phone us with the details and we will match or better it, and can provide the fitting kits.