Flues

A Solid Fuel AGA requires some form of flue or chimney, so as to safely remove the natural smoke and combustion fumes, at the same time taking cooking smells and steam from the ovens.

For the AGA to work properly, the chimney must be constructed of the the appropriate materials and rise to a satisfactory height, whilst complying with current legislation, such as the Building Regulations.

The need for access to a chimney will probably dictate the position chosen for the AGA, and we would strongly advise that your local AGA Distributor be asked to carry out a survey of the proposed site.

Two main chimney arrangements are available (see illustration below):

• To use a masonry chimney, suitably lined with an appropriate material and terminating at a height above the main roof ridge. The lining must be of at least 150mm diameter.
• Where no convenient chimney exists, it is possible to use a twin walled, factory insulated, prefabricated, stainless steel chimney system, such as ‘S.M’ from Selkirk

Whichever arrangement is chosen there are several requirements common to both:

• Means for sweeping the chimney must be provided i.e. a soot door
• No flue sharing with other appliances
• Bends to be kept to a minimum and must not be less than 135 degrees from the vertical.
• For aesthetic reasons, black vitreous enamelled, single skin, cast iron pipe may be used to connect between the AGA and the main chimney. The pipe will be 100mm diameter, rising vertically from the top of the AGA, before bending at 45 degrees into the chimney, where necessary. Single skin pipe must not extend outside of the kitchen area.
• Alternatively, it is sometimes possible to use a rear connection from the AGA, horizontally through the rear wall and into a chimney situated immediately behind. The horizontal pipe must be no longer than 150mm, i.e. the thickness of a single brick.

Ventilation

Like all solid fuel appliances, the AGA requires a permanent air supply into the kitchen to provide both air for combustion and also to enable the chimney to operate.

A permanent opening of 30 sq.cm free area is required and normally a 6" x 9" brick will provide this amount. Extractor fans and cooker hoods do not give a supply of air into the room, as they are busy sucking it out, as do other appliances such as a tumble dryer.

If other combustion appliances are fitted in the same room as the AGA, then additional ventilation will be required.

Plumbing

With the 2 oven model AGA, you have the option of obtaining domestic hot water.

This provides an economic way of producing 410 litres (90 gallons) of hot water, spread out over a 24 hour period, regardless of how much cooking is carried out.

Hot water is generated within the AGA and circulates through a conventional, open vented, gravity system into a 190 litre storage cylinder, located within 5 metres of the AGA.

Does the AGA produce domestic hot water for free?
There is a slight increase in the fuel consumption of a boiler model, but it is still an economic way of obtaining hot-water.

Will the hot water demands affect the AGA’s cooking performance?
No. The boiler draws its heat indirectly from the burner chamber/ fire-barrel.

What happens if we do not use all the hot water produced by the AGA?
There will be an increase in the temperature of the domestic hot water, but overheating is unlikely under normal circumstances.

What if we need more hot water than the AGA will produce?
There is no reason why an electric immersion heater cannot be fitted to the cylinder, for occasions when top-ups are required. Alternatively, it is sometimes possible to interconnect the AGA into a ‘shared system’ with another boiler or heat source. Special controls and plumbing arrangements will be required, and the AGA must be allowed to contribute the bulk of the heat required. A special ‘ twin coil’ cylinder is often used in such circumstances.

Can we fit a thermostat to the AGA to control the hot water temperature?
No. If there are concerns regarding the upper temperature limit, then consider fitting a mixing valve at the cylinder outlet.

Can the AGA be used to supply a radiator?
The AGA is designed to release just enough heat from its boiler to generate 90 gallons of hot water over 24 hours. Fitting even a small radiator would seriously reduce the amount of domestic hot water available.

What about a towel rail?
As above, fitting a towel rail will reduce the hot water production. In some households, this might be useful, if demands for hot water are limited, in which case, the towel rail will act as a heat-leak.

What happens in a hard water area?
The plumbing system for an AGA should be of the ‘indirect’ type, in which case lime-scale will not be a problem. Older AGA’s may have been connected to ‘direct’ systems and may require occasional de-scaling, if the boiler becomes noisy.

Can the AGA be connected to a ‘sealed’ hot water system?
An AGA must be connected to a vented system, with an appropriate feed and expansion tank. Some proprietary ‘Thermal Store’ cylinders may be connected to an AGA, such as the ‘Mainsflow’ from Albion cylinders. This allows the hot water to be at mains pressure. Further details of this type of system and the necessary controls required, should be obtained from the relevant cylinder manufacturer.

Can a boiler be fitted to an existing ‘dry’ AGA?
Recent AGA’s can usually have a boiler added fairly easily. Ask your AGA Distributor for more details or a quotation.

We no longer want hot water from our AGA. Can we just disconnect the boiler?
To make the AGA safe, the boiler will need to be removed and insulation material put in its place, to maintain efficiency. This work is fairly straightforward, please ask your AGA Distributor for further details.

The water supply to the house is to be off for a short while. What should we do?
The AGA may be left on, preferably with the thermostat turned down low. Do not draw any hot water out of the taps. If the water is likely to be off for more than a few hours the fire should be let out.

Hearth

When choosing a site for an AGA, there are a number of factors to consider which will influence its positioning.

Flue/Chimney
May require the AGA to be close to an existing chimney or AGAinst an outside wall. See separate sheets on flues/chimney/ventilation.

Floor/Hearth/Plinth

• The floor must be strong enough to carry the weight of the AGA, typically :- 2 Oven 480kg (9.5cwt) 4 Oven 635kg (12.5cwt)
• Where an AGA Electric or Gas Module is attached add 129kg (2.5cwt)
• The hearth must be non combustible for a thickness of at least 125mm

A raised plinth is not essential, and there is no reason why an AGA shouldn’t sit on the normal floor ( providing it meets the above criteria) If a higher working position is preferred, or the finished height needs to match adjacent work surfaces, then a cast concrete slab, usually 50mm thick, is the answer. The slab dimensions should be the same as the base of the AGA:

• 2 oven 987 x 679mm
• 4 oven 1487 x 679

The 679 dimension can be reduced slightly if the front of the plinth is to be tiled. Whatever type of hearth is chosen, it must be absolutely level in all directions.

Clearances

In most case, work units can be brought right up to the sides of the AGA, without the risk of damage from heat. Work tops should however stop short of the AGA top plate and not actually touch it. Any slight gap can be filled with a silicone sealant. If the surrounding walls are to be tiled, then this must be done before the AGA is installed, as the tiles must be taken down below the AGA top plate level, not finish above it.

The rear wall must be non combustible for at least 200mm thickness.

In a recess situation, If the adjacent right-hand wall protrudes forward beyond the front of the AGA, then an additional width clearance is required of 116mm on the right hand side, to allow the oven door to be opened sufficiently.

If the AGA is to be installed in a brick recess, then the minimum clearances should be increased by at least 10mm on either side, to allow for the walls being out of square and also for the natural dimensional variations found in castings.

At least 60mm clearance should be allowed above the insulating covers in their vertical, open position.

AGA Dimensions

Maximum depth over handrail etc 756mm
Maximum width, 2 oven 987mm, 4 oven 1487mm (see note above)
Maximum height with insulating lids open 1330mm (see note above).

Heat to Room

The AGA releases a gentle warmth into the kitchen, which is not likely to give rise to any problems, unless the room is exceptionally small or poorly ventilated. The actual output varies slightly from model to model and in accordance with the type of flue system chosen. An average contribution to the room of 1 kW/hr should be allowed.

Fuel

See the list of approved fuels. Bear in mind that the fuel must be stored under cover and kept dry.

* See also the pages covering Flues & Ventilation and Domestic Hot Water requirements

IMPORTANT. All AGA’s must be installed in accordance with current legislation, such as the Building Regulations, Industry Standards etc.. Please refer to the main Installation Instructions for this product , regarding further information.