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Conder Bypass Oil Separator CNSB25S/21 - up to 13889m2
£2,190.00
Direct Drainage Reviews

The Conder range of Bypass Separators are used to fully treat all flows generated by rainfall rates of up to 6.5mm/hr. Bypass Separators are used when it is considered an acceptable risk not to provide full treatment for high flows, for example where only small spillages occur and the risk of spillage is small.

Typical applications include car parks, roadways and major trunk roads, light industrial and goods yard and where discharge is to a sensitive environment.

Alarm Options


Environment Agency PPG3 Guidelines stipulate that all separators must be fitted with a robust system to provide an audible and visual alarm if the oil level becomes too high. We strongly recommend that you purchase the High Oil Level Alarm alongside this item, and it will be delivered with the separator ready to wire in.

Alarm options include the Darcy indoor oil alarmDarcy outdoor oil alarm, Darcy battery-powered GSM alarm or Darcy solar alarm

Features and Benefits



  • Innovative design makes it extremely compact for easy handling and installation.

  • CNSB Bypass Separators are designed and tested in accordance with BS EN858-1-2 and are proven to separate oil and water under tests to less than 1 parts per million, and therefore protect both the environment and public safety.

  • Designed to treat all flow up to the designated nominal size. Any flow in excess of the nominal size is allowed to bypass the separation chamber, thereby keeping the separated and trapped oil safe.

  • Free delivery - you will need to organise your own offloading

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