摘要 |
The liquid flowing through a heat circulation system including a boiler can be maintained in an air absorbing condition even at the highest elevation in the circulation system. The air absorbing condition is attained by alternately subjecting the liquid in the boiler to the high pressure of the circulating system and at least to atmospheric pressure and effecting deaeration while the liquid is at atmospheric pressure. During deaeration the liquid is blocked from flowing from the boiler into the circulation system. Following deaeration, the liquid is brought up to the high pressure of the system before it is directed back into the system. |