Question: What type of gas fire can I have in my home?

Answer: This depends on Flue Type

What type of flue do I have?

Class I

A property older than 1960 will usually have this type of flue. It will be a brick built chimney, suitable for a solid fuel fire and can be identified by the clay fire back or “chair brick” at the base of the opening. It will have a minimum diameter of 7” (175mm) and will terminate to a clay pot or cowl. The majority of fires are suitable for this type of flue.

Class II

There are two main types of this flue:

An older property where the chimney is unsound will be lined with a 5” (125mm) flexible steel flue lining, which will be sealed at the top and bottom. This will terminate to a gas cowl. This type of flue is not suitable for a solid fuel fire or open basket. A modern property without a chimney may well have a 5” (125mm) rigid sectional steel flue system. This will terminate through a short length of steel pipe to a gas cowl. This type of flue is not suitable for a solid fuel fire or open basket

Pre-Cast Flue

Most modern properties will have this type of flue. It is a sectional concrete flue block system and can be identified by the starter block or letter box at the base of the opening. This terminates to a purpose made raised roof ridge tile. This type of flue is not suitable for a solid fuel fire or open basket.

No Chimney or Flue

If there is no chimney or flue, the following options are available:

Question: What is a Power Flue/Balanced Flue/Flueless gas fire?

Balanced Flue fires are glass fronted and need to be fitted to an outside wall. These fires can be wall mounted or fitted to a fireplace. Fan-flue or Power flue fires offer the beauty of an open fronted fire with “real” flames without the need for a chimney or flue.

These units are supplied complete for installation to a suitable outside wall; an electrical supply will be required. Catalytic or Flueless fires do not require any chimney or flue or even an outside wall; these fires use the latest in gas fire technology and can be installed virtually anywhere – the combustion gases produced by the fire pass through a catalytic converter within the appliance which converts the poisonous Carbon Monoxide into harmless Carbon Dioxide and water vapour.

Question: I haven’t got a chimney; can I still have a wood burning or multi fuel stove?

Yes; but only with provision of a flue. If your room doesn’t have a chimney, it doesn’t mean that you can’t have a stove but you’ll need to have a twin wall insulated flue installed.

To see what is required to fit a stove into a room without a chimney, and where it isn’t possible to take the flue outside, please read the guide.

Fitting a stove with internal twin wall insulated flue system:

To see what is required to fit a stove into a room without a chimney where it is possible to take the flue outside and up an exterior wall, please read the guide.

Fitting a stove with external twin wall insulated flue system.

Installing an external twin wall insulated flue system

This will depend on the situation into which the stove is being installed. On provision of a drawing of the room in question, our experts can assist in designing the appropriate flue system.

A basic install would require the following: (this is to give an idea of what may be required and will not necessarily be the samefor all situations)

  1. Stove
  2. Vitreous Enamel Flue Pipe (*see notes)
  3. 45 degree bend
  4. Single skin to twin wall insulated flue adaptor
  5. Twin wall insulated flue (500mm to go through the wall)
  6. 45 degree T shape bend with soot door
  7. Wall Bracket (These are required every 2m to help support the flue system)
  8. 2 x 45 degree bend (for taking the pipe around the gutter and may not be necessary)
  9. Length of twin wall insulated flue pipe (See below to calculate required length)
  10. Rain cap (if the overall length of the flue system is less than 4m, we advise that using an aspirating cowl to guarantee a draw)

Notes:

* You must go up vertically 600mm before you can go through the wall.

Two important guides which must be followed when calculating the height to take the flue are:

a) If the flue is sited close to the ridge or gable end, the pipe must clear the ridge by at least 600mm.

b) If the flue is comes out through the roof, away from the ridge or lower down the roof, then the flue must be at least 2.3m horizontally away from the nearest point on the roof line.

This guide is designed to give guidance with regard to the installation of a stove and flue system. It is not recommend that this be attempted by an unqualified person. A professional HETAS installer should always be consulted.