Description

The monument consists of the remains of a Guibal Fanhouse that was built to ventilate the Ynysgedwyn Colliery in the late 19th century. The building consisted of a rectangular stone chamber with a tower at one end topped with a yellow brick evisee through which the air was expelled. The chamber was circular in longitudinal section and contained a rotary fan operated by the steam engine adjacent to it. The sides of the chamber have been demolished or collapsed at the end furthest from the evisee, while the remaining section of the roof is lined with planks. Yellow brick bearings near the centre of the circle carried the central shaft of the fan and there is a continuous runner set into the stonework marking the outer edges of the blades. The development of mechanical ventilation in coal mines was crucial to the improvement of safety and the extension of working potential during the late 19th century. The Guibal Fan was one of the earliest to come into general use and was the most successful, with nearly 200 installed within 14 years of it being patented in 1862. This is the only known Guibal Fanhouse to survive in Wales and one of only four surviving in the UK as a whole. The site is currently in a ruinous condition.

The monument is of national importance for its potential to enhance our knowledge of mining in Wales. It retains significant archaeological potential, with a strong probability of the presence of associated archaeological features and deposits. The structure itself may be expected to contain archaeological information concerning chronology and building techniques. A fan house may be part of a larger cluster of industrial monuments and their importance can further enhanced by their group value.

The scheduled area comprises the remains described and areas around them within which related evidence may be expected to survive.

Source: Cadw