Heating the heat inside the building is many industrial processes and energy necessary . Assuming every processing program and a separate room for each room heating needs are , if separately for each unit to be heated frequent heat, so the heat generated by the friction heat than many independent heating system will generate a multi - of course, the premise is efficiency can not be too low. For this reason, upon heating unit usually consists of central heating and by the transmission medium - to - we call it the heat carrier. The carrier will transport each heat to consumers , the carrier will be returned after cooling to heating center once again heating cycle work.

As a heat carrier, water and steam has many excellent properties , such as : high energy absorption and transport facilitation : everywhere to be found ; environmental pollution ( unless you pour boiling water parterre , then the flowers are certainly not survive ) ; at atmospheric pressure a relatively low boiling point , of course , if the desired temperature is higher than 100 ° C , pressure needs only to carriers , the boiling point is increased.

Each pressure cooker is the use of this physical principle , for example, to ensure that the pressure cooker lid sealed , so the boiling point ( in 1BAR atmospheric boiling point is 100 degrees Celsius ) could not produce steam leakage . Thus, the increase in pressure pot , while the boiling point increases. If the pot is higher than the pressure of about atmospheric pressure through the valve adjusted 1BAR, then the pressure pot temperature is not as common as open pan 100 degrees , but 120 degrees Celsius, so the food will cook faster .

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