The design and construction of these boilers is based on the international standard BS 855, which is under the supervision and inspection during the construction of the Iranian Institute of Standards and Industrial Research, which is reviewed and quality controlled during several stages. » These models of boilers are able to produce water from 70 to 99 degrees Celsius and their working pressure is from 4 to 10 atmospheres and they are made in capacities of 100,000 KCAL/h to 2,000,000 KCAL/h. » If needed, this product is delivered as a complete package with equipment such as non-return valves, thermometer, safety valve, and control and electrical equipment according to the customer’s needs. The advantages of using return flame spa boilers of Bohar Gostar company (metal boiler):