*及Eheim 濾桶只建議關細出水閘減慢水流的原因...
上次討論關於濾桶減慢水流應關細出水閘還是關細入水闡,
基於關細出水閘會令桶內壓力上升的理論,
一般想信有可能會引至濾桶漏水,
所以一般都想信應只關細入水閘減慢水流是正確的.
但有網友提出Eheim 濾桶說明書只建議關細出水閘減慢水流,
究竟是錯印還是有其它原因呢?
討論最後也沒有一個比較合理的答案出現.
基於好奇及求知心態....(說穿了只是八公心態 :p)
我又嘗試email這問題到德國Eheim,
但一星期都沒有回應,
我再email這問題到Eheim Asia (星加玻)
二日後得到了回應...
說出他們的理論, 在此和大家分享研究一下
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Eheim的理論是:
如關細入水閘會令桶內壓力過低, 引至已溶在水中的空氣再生成氣體,
引至的問題是當氣體經過泵頭時產生嘈音,
而嚴重時, 當大型氣泡經過泵頭時甚至會令水流停止,
而水流停止再會引至泵頭過熱.
因此Eheim 只建議關細濾桶出水閘來減慢水流,
但只建議關細最多至50%位置以防水流停留在泵頭過久, 因這同樣會引起泵頭過熱.
Eheim指出他們的濾桶設計上是可承載關細出水閘位引起的桶內壓力增加而不會漏水,
反而過份關細入水位(如關90%)所引起的桶內壓力過低就有可能會引至漏水...
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真是好有理據支持, 各有各的道理...
特別是關細水閘(出或入)所引起的問題都有代大家思考...
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原文:
By closing the suction side (inlet) you can get an under-pressure in the
container. This may set free air which is dissolved in the water.
The corresponding problem which could result is that there will be noise
which may be created when the air passes through the pump. In the worst
case, the air builds up into a big bubble and when this big bubble passes
through the pump, due to the air pocket, the water flow could stop resulting
in over heating of the filter.
Therefore we recommend only to close the pressure side (outlet). We
recommend only to close up to only 50% of the output valve, so as to avoid
the recycling of the same water around the pump head resulting in
overheating as well.
Leakage is not an issue, as Eheim canister are made to withstand this
pressure. On the contrary, if there is huge under-pressure in the canister
(eg. Suction side is being closed to 90%), a resulting leakage could occur.
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