Conder Clereflo Bypass Separator: Area up to 2500 sq/metres

Premier Tech Aqua/Conder

Regular price £960.00

The CNSB4.5S/21 is suitable for an area of up to 2500 sq/meters

Bypass separators fully treat all flows generated by rainfall rates of up to 6.5mm/hr. These 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 such as on short stay car parks.

Features and benefits:

  • Innovative design
  • Small and easy to handle
  • Competitively priced
  • Fully compliant to the Environment
  • Agency’s PPG3 guidelines
  • Major installed cost savings
  • Fully tested and verified with a range from CNSB 3s to CNSB 1500s (class 1)
  • Full BSI certification
  • Exceeds industry standards
  • An Environment Agency verified manufacturer
  • Easy to service

Process & performance

The Conder range of bypass separators is designed to treat all the flow up to the designed nominal size. Any flow more than the nominal size can bypass the separation chamber thus keeping the separated and trapped oil safe. During the early part of a rain storm which is a time of high oil contamination, all the contaminated water flow passes through a sediment collection chamber and enters the separation chamber through a patented oil skimming and filter device. This ensures that all the oil proceeds to the separation chamber where it is separated to the Class 1 standard of 5mg/l and safely trapped. As the rain storm builds up to its maximum and the level of oil contamination reduces significantly, the nominal size flow continues to pass through the separation chamber and any excess flow of virtually clean water can bypass directly to the outlet.

Application areas:

  • Car parks
  • Roadways and major trunk roads
  • Light industrial and goods yards
  • Discharge to sensitive environment


  • Length - 1.7m
  • Dia - 1m
  • Height - 2.8m
  • Access - 600mm
  • Base to inlet - 1.2m
  • Base to outlet - 1.2m