| 摘要 |
<p>The container has two separate chambers, arranged one above the other. The upper chamber contains a non frost protected fluid and the lower chamber contains an anti-freeze liquid. The two chambers are connected by an external pipe. The liquid in the external pipe freezes during frost conditions allowing the anti-freeze liquid only to be used. Alternatively a container with three separate chambers could be used. The anti-freeze chambers are provided with an over flow protection consisting of a non return valve. The valve permits air to enter the chamber but prevents liquid leaving.</p> |
