Overview

We are seeking a skilled and experienced Pre-Commissioning Water Treatment/Flushing Engineer to carry out pre-commission cleaning, chemical dosing, flushing, and water treatment for closed-loop and open systems (CHW, LTHW, condenser, domestic water, etc.). This role ensures systems are delivered to specification, compliant with BSRIA BG29/BG50, and fully prepared for commissioning and handover.

Main duties:

  • Perform pre-commission cleaning, dynamic and static flushing, chemical dosing, and sampling of HVAC and water systems in accordance with BSRIA and project specifications.
  • Carry out closed and open loop water system flushing (e.g., CHW, LTHW, condenser, domestic hot & cold water).
  • Conduct system water quality testing, interpret results, and make chemical treatment adjustments accordingly.
  • Complete on-site testing including pH, conductivity, iron, hardness, and bacteria sampling (Legionella, TVC, etc.).
  • Maintain accurate documentation and produce reports such as flushing certificates, test results, and compliance records.
  • Coordinate with mechanical and commissioning teams to ensure timely execution of pre-commissioning activities.
  • Operate pumps, dosing rigs, side stream filters, and other related equipment.
  • Ensure flushing and chemical cleaning operations comply with HSE regulations and COSHH guidelines.
  • Troubleshoot and resolve water quality or system performance issues on-site.
  • Attend client/site meetings and provide technical input on water treatment processes when required.

The ideal candidate will have the following:

  • Proven experience (2+ years) in water treatment, pre-commission cleaning, or mechanical flushing.
  • Strong working knowledge of BSRIA BG29 & BG50 guidelines.
  • Familiarity with HVAC systems, pipework layouts, strainers, valves, and test points.
  • Experience handling water treatment chemicals, including inhibitors, biocides, and cleaning agents.
  • Ability to use and calibrate basic water testing equipment.
  • Excellent documentation, communication, and report-writing skills.
  • Full, clean driving license and willingness to travel to sites as needed.
  • Safe Pass card required; additional site certifications (e.g., confined space, MEWP) are a plus.

Preferred Experience

  • Experience on large-scale data centre, commercial, life science, industrial, or healthcare construction projects.
  • Knowledge of closed loop, domestic systems, cooling towers, or cleanroom water treatment.
  • Legionella awareness training or water hygiene qualification.
  • Understanding of commissioning timelines and coordination with mechanical packages.
  • Experience supervising or mentoring junior technicians or subcontractors.

What We Offer

  • Competitive salary and allowances.
  • Opportunities for certification and training (BSRIA, LCA, etc.).
  • Work with leading clients in data centers, pharma, commercial, and healthcare sectors.
  • Supportive team and opportunity for career progression.
  • Company vehicle and travel expenses (if applicable).