020 4548 4226

HIU Service London — Specialist Heat Interface Unit Servicing

Looking for a reliable HIU service in London? Collide Group is London's dedicated Heat Interface Unit service specialist — annual HIU servicing from £120 inc VAT, carried out by manufacturer-trained engineers. We cover every major HIU brand including Danfoss, SAV, Switch2, Caleffi, Alfa Laval, Heatweb, Thermal Integration and Redan, with same-week appointments across all London boroughs.

Get a Free Quote 020 4548 4226

Why HIUs Need Annual Servicing

Heat Interface Units handle high temperatures, scale-prone water, and constant duty cycles. Without servicing, plate exchangers fur up, strainers clog, actuators stick, and efficiency drops by 15–25% over a few years — driving up bills and risking failure at the worst possible moment.

  • Limescale build-up on plate heat exchangers
  • Clogged primary and secondary strainers
  • Sticky control valves and PICVs
  • Drifting temperature sensors and actuators
  • Sludge accumulation reducing flow
  • Failing seals and worn isolation valves

A Full HIU Service, Done Properly

Our engineers follow a manufacturer-aligned service schedule for every brand. We don't just tick boxes — we measure performance, clean what needs cleaning, and report exactly what we found.

  • Visual and operational inspection of the full unit
  • Strainer clean and primary filter check
  • Plate heat exchanger descale (where needed)
  • PICV, actuator and DHW valve test
  • Temperature, pressure and flow performance check
  • Written service report with photos and recommendations

Brands We Cover

DanfossSAVAlfa LavalCaleffiSwitch2HeatwebThermal IntegrationRedan

Related HIU work in London: HIU Repair London · HIU Installation London · Bulk Servicing London · HIU Powerflush London · All HIU Services

The Benefits

Lower Energy Bills

A clean, well-tuned HIU runs cooler and uses less primary energy — savings residents notice.

Fewer Breakdowns

Catch faults before they become emergencies. Annual servicing typically prevents 80% of unplanned callouts.

Longer Lifespan

Serviced HIUs routinely last 15+ years. Neglected ones often need replacement in under 10.

500+
“We've had Collide service almost all the HIU's in our 60-flat block. Callouts have dropped massively and residents are happier than ever.”

— Managing Agent, Tower Hamlets

Annual Service from £120

Single-flat HIU service from £120 inc VAT. Discounted block rates available for property managers — see our bulk servicing page.

Request a Written Quote

Frequently Asked Questions

How often should an HIU be serviced?
Once a year is the manufacturer recommendation for most HIUs. Annual servicing extends lifespan, maintains warranty and prevents the majority of breakdowns.
How long does a service take?
A standard single-flat HIU service takes 45–60 minutes. Bulk servicing across a block is usually completed in batches over one to three days.
What's included in your service?
Visual inspection, strainer clean, valve and actuator testing, performance measurement, descale where needed, and a written report with photos.
Do you service HIUs under manufacturer warranty?
Yes — our engineers are trained across all major HIU brands and follow manufacturer service schedules, keeping your warranty intact.
Will residents need to be home?
Yes — we need access to each flat for around an hour. We coordinate with you on appointment slots and can offer evening or Saturday slots for blocks.

Related HIU Services

HIU Repair

Same-day fault diagnosis and repair across London.

Learn more

HIU Installation

New-build and replacement HIU installs, all brands.

Learn more

Bulk Servicing

Block-wide service contracts for property managers.

Learn more

HIU Powerflush

Remove sludge and scale to restore HIU performance.

Learn more

Book Your Annual HIU Service

Speak to a specialist HIU engineer today. Free quotes, transparent pricing, no obligation.

Book HIU Service Call 020 4548 4226