Throughout Iran, in general and in hot and dry areas, especially in hot summers with unbearable heat, ice has always been a necessity of the people, which in addition to cooling drinking water, is also used to preserve food.
The construction technique and architectural style of Yakhchals (Ice Chambers) should be responsive to issues such as building insulation and maintaining proper refrigeration to store ice.
Refrigerators consist of three parts:
1- Long shading wall
2- Ice production ponds
3- Ice tank
1- Shading wall
The shading wall is a very long wall that stretches from east to west. The high height of these walls Occasionally up to 10 meters, prevents the sun from shining on the frozen water in the ponds during the day. To reduce the pressure on the foundation along the wall, several arches were constructed which, in addition to helping the wall to stand, create a light shadow on the wall facade and reduce their uniformity.
Sometimes, in order to strengthen the wall, large supports were constructed in the southern part of the wall.
2 - Ice ponds:
A Rectangular pit is drilled parallel to the shading wall and in its northern part . its length is slightly less than the length of the wall . its depth is 30 to 50 cm and sometimes more. This pit was the place to prepare ice on cold winter nights, so that in winter nights they were filled with water and in the mornings, after the water had frozen, natives cut the ice into pieces and collected them in tanks.
3. Ice Reservoirs:
These reservoirs are usually located behind the wall and in its southern part, and are accessed by one or more entrances to the northern part and towards the ice ponds.
The walls of these pits were made of stone or brick lined with thatch and the back was covered with insulating materials such as charcoal or other materials. To reach the floor of these pits, small stairs were built into the wall. Because moisture and water from melting ice could seep into the bottom of the glacier and have a devastating effect, architects dug a well outside the Yakhchal to prevent this erosion and installed it through narrow ducts at the bottom of the ice pits. Water from melting ice was directed to these wells.
Producing and using ice:
To prepare the ice, ponds built at the foot of the canopy wall were filled to a certain level with water on cold winter nights. The extreme cold of the night caused the water in these ponds to freeze. The amount of water that was directed at these frozen masses the following nights was so great that the cold of one night could freeze it. In general, the height of the water on the previous ice surfaces did not exceed a few centimeters, and this was repeated until the diameter of the ice reached the depth of the ponds.
In some desert areas, it was covered with a layer of mud. Then, the entrances of Yakhchal were sealed and all the holes were closed by thatching on it. When the weather warmed up and it was necessary to use ice, the icebreakers, with their boots and rubber tops and iron claws, pulled the ice cubes out of the pit . They were brought to the adjacent room. these rooms, which were located at the exit of the Yakhchal, were opened only in the morning or at sunset. gradually the ice was broken and taken to the market for sale. These Yakhchals had ice in all seasons.
