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Solution · Cooling systems

Cooling Water Filtration

Cooling circuits accumulate suspended solids, scale particles and airborne debris that foul heat exchangers and narrow-clearance components. High-flow side-stream filtration continuously removes this particulate load, keeping heat-transfer surfaces clean and protecting downstream equipment such as CDUs in liquid-cooled data centres.

Where in the process

Installed as a side-stream loop on the cooling circuit (open tower or closed loop), continuously filtering a slipstream of the circulating water. It targets particulate; it is not a chemical-treatment substitute.

What goes wrong without adequate filtration

  • Suspended solids and scale particles foul heat exchangers, quietly eroding heat-transfer efficiency and raising energy cost
  • Airborne debris drawn into open towers accumulates and blocks nozzles and narrow-clearance components
  • Fouled CDUs and cold plates in liquid-cooled data centres risk thermal throttling of critical equipment
  • Without a particulate barrier the circulating load keeps climbing between water changes

How it works

  1. 1

    Tap a slipstream

    A fraction of the circulating cooling water is diverted continuously through the high-flow filter rather than filtering the full flow.

  2. 2

    Capture the particulate

    The element removes suspended solids, scale particles and airborne debris from that slipstream on every pass.

  3. 3

    Polish the whole circuit

    Over many passes the circulating load falls, keeping heat-transfer surfaces and narrow clearances clean.

  4. 4

    Low, stable ΔP

    A large element holds a high dirt load at low pressure drop, so the side-stream pump stays efficient between services.

Typical filtration requirements

  • Continuous removal of suspended solids, scale particles and debris
  • Low pressure drop so the side-stream pump stays efficient
  • High dirt-holding capacity for long intervals between service
  • Protection of heat exchangers, nozzles and cooling-distribution units

Why high-flow wins here

1A single large element replaces many small cartridges on the slipstream
2Fewer change-outs — important for continuously running cooling plant
3Stable low pressure drop protects side-stream pump efficiency
4Configurable housing for open-tower or closed-loop installations

Selection & sizing factors

Micron rating
Often the mid-particulate range, balancing solids capture against pressure drop and service interval.
Circuit type
Open tower (airborne debris, higher load) versus closed loop (finer polishing) changes rating and dirt-holding.
Slipstream flow
The diverted fraction sets the element and housing size for effective circuit polishing.
Protected component
Heat-exchanger channels, nozzles or CDU cold plates set the finest clearance the rating must protect.

Sizing & selection

Side-stream cooling filtration is often specified in the mid-particulate range, balancing solids capture against pressure drop and service interval. The right rating depends on the circuit’s fouling profile. Tell us the slipstream flow and the components you are protecting — we recommend element and housing.

The right housing for this solution

A side-stream housing is sized to the slipstream, not the full circuit flow, which keeps it compact and easy to retrofit onto an existing cooling system. We configure the housing for an open-tower or closed-loop installation with the right connections and material, and supply the matching high-flow elements. Use the housing configurator to specify a side-stream skid or replacement vessel.

Operational impact

Cleaner heat-transfer surfaces preserve cooling efficiency and cut energy cost
Fewer change-outs suit continuously running cooling plant
Compact side-stream footprint retrofits into existing systems
Protected exchangers, nozzles and CDUs mean less unplanned downtime

Relevant industries

Frequently asked questions

What is side-stream filtration?

A side-stream (slipstream) filter continuously treats a fraction of the circulating cooling water. Over time the whole circuit is polished, removing suspended solids without filtering the full flow.

Does this replace cooling-water chemical treatment?

No. Mechanical filtration removes particulate; scale and corrosion control still rely on the water-treatment programme. The two work together.

Is it suitable for liquid-cooled data centres?

Yes — side-stream high-flow filtration protects CDUs and cold plates from particulate that would cause thermal throttling. We size it to the loop and the clearance you must protect.

Open tower or closed loop — does it matter?

Yes. Open towers pull in airborne debris and carry a higher load; closed loops need finer polishing. We set rating, dirt-holding and housing to the circuit type.

The right solution for your process?

Tell us your flow rate, medium and target rating — we recommend the element and, if required, the matching housing.