MODERN COAL APPLIANCES EFFICIENT, ECONOMICAL

Press, Volume CVI, Issue 31349, 20 April 1967, Page 24

MODERN COAL APPLIANCES EFFICIENT, ECONOMICAL

Many years ago coal or wood burned in open fireplaces was the only available means of heating the home. Today other forms are used, but coal still retains a 60 per cent share of this market.

Two factors contribute to the lasting popularity of coal as a heating fuel: first, it can now be used with much higher efficiency in a wide variety of appliances which can be installed in any home, whether it be of the traditional or ultra-modern design.

Second, there is an appealing quality about the cheery glow of a coal fire which suggests friendly warmth and comfort.

The life of most homes has always revolved around the hearth. Realising this, research engineers have provided modern designs of coal fires that incorporate maximum efficiency with a minimum waste and still retain the heart-warming glow. Proper design of the throat of the chimney, care-

fully sealed fronts to the grates and control of the air flow to suit the rate of burning are now the pattern of all modern installations. Increasing in popularity is the convector type of coalfired unit In some models the fire is framed by an attractive enamel surround. In other models the only

apparent difference from the traditional open fire Is the louvres admitting warm air into the room. For high efficiency, closed stoves are available. These can be inset into a surround or used free-standing. Where air heating is required on a large scale, hot air furnaces capable of supplying 70,000 B.T.U.s an hour are available. Air is circulated by a silent fan through ducts from a heat

exchanger which is warmed by the hot gases from a mechanical stoker-fed furnace.

Most of these appliances will provide adequate hot water for all domestic uses by fitting a back boiler. A new type of open fire—-whole-house central heating —has recently been placed on the market. With this model a boiler designed on the fire-tube principle is fitted into the. existing open fireplace. Four tubes that pass longitudinally through the boiler form the flue passage to the chimney, thereby increasing the normal water heating area. Hot water is then pumped through small-bore pipes by an electric accelerator pump to slim steel radiators in other rooms and to a towel rail in the bathroom. The boiler also provides abundant hot water for domestic use.

switched off entirely when hot water alone is required. The damper also gives control over the fire and the quantity of fuel required. This system is supplied by the manufacturers in kit form and can be installed either in an existing or new home. While the thoughts of the homemaker are restricted to heating units of a much smaller size, great interest has been aroused in Christchurch by the manufacture by a local firm of the two largest coal-fired boilers ever made in New Zealand for installation at the University of Canterbury. Dwarfing a modern car, the boilers are each 12ft 6in diameter, 26ft 6in long overall, and weigh 32 tons. In order to keep coal consumers and potential consumers fully advised on the latest technological advances in burning, firing and storage, the New Zealand coal industry maintains a free advisory service by fully qualified engineers. The service includes advice on the operation of existing plant, choice of new plant, suggestions for improving the performance of equipment, home heating systems, and the production of literature on industrial and domestic heating.

A sliding damper control can be adjusted to suit the requirements of both room heating and domestic hotwater supply. The centralheating system can be