Commercial Hot Water System Pre-Winter Checklist

Why Pre-Winter Servicing Matters

As temperatures drop, commercial hot water systems face increased demand and greater risk of failure. Proactive servicing helps prevent:

  • System breakdowns during peak usage
  • Frozen pipes and water damage
  • Energy inefficiency and rising costs
  • Non-compliance with health and safety regulations

Regular maintenance also supports legionella prevention, ensures temperature monitoring is accurate, and helps avoid costly emergency repairs. For facilities managers and compliance officers, pre-winter servicing is a smart, cost-saving strategy.

 

Key Compliance Requirements for Commercial Hot Water Systems

HSE Legionella Control (L8)

  • Maintain hot water at ≥60°C and cold water below 20°C
  • Implement flushing regimes for infrequently used outlets
  • Conduct regular temperature checks and risk assessments

 

Water Regulations and Safety Standards

  • Follow BS 8558 for water system design and maintenance
  • Comply with Part G of the Building Regulations for sanitation and hot water safety

 

Record-Keeping Obligations

  • Maintain logbooks of inspections, servicing, and temperature checks
  • Ensure documentation is audit-ready and accessible
  • Store digital copies for compliance and insurance purposes

 

Step-by-Step Pre-Winter Servicing Checklist

Inspect and Test Immersion Heaters

  • Perform continuity and resistance testing
  • Check thermostat calibration and safety cut-outs

 

Flush and Clean Cylinders and Pipework

  • Remove sediment and scale buildup
  • Improve heat transfer and water quality

 

Check for Corrosion or Leaks

  • Inspect tanks, pipework, and valves
  • Address early signs of wear before failure

 

Test Safety Valves and Controls

  • Verify pressure relief valves and expansion vessels
  • Ensure over-temperature protection is functional

 

Confirm Correct Temperature Settings

  • Storage temperature should be ≥60°C to prevent legionella
  • Avoid scald risk by balancing outlet temperatures

 

Review System Insulation

  • Check lagging on pipes and cylinders
  • Prevent heat loss and pipe freezing

 

Verify BMS and Control Systems

  • Ensure timeclocks and sensors are programmed for winter demand
  • Test remote monitoring and alert systems

 

Improving Efficiency Before Winter

  • Balance temperature settings for compliance and energy savings
  • Upgrade to smart thermostats or energy-efficient immersion elements
  • Insulate pipework and cylinders to reduce heat loss
  • Check flow rates to avoid wasting hot water

 

When to Involve a Qualified Engineer

Some tasks require certified professionals:

  • Electrical work and wiring
  • Pressure vessel inspections
  • Gas boiler servicing
  • System commissioning and certification

Schedule annual service visits before peak winter demand to ensure uninterrupted operation.

 

Documentation and Compliance Records

Stay audit-ready by:

  • Keeping up-to-date service reports and temperature logs
  • Storing digital copies for easy access
  • Documenting risk assessments and corrective actions
  • Demonstrating compliance for insurance and health & safety audits

 

FAQs on Commercial Hot Water System Servicing

How often should commercial hot water systems be serviced?
At least annually, with additional checks before winter and after any major system changes.

What is the minimum hot water temperature for legionella prevention?
60°C at the cylinder and 50°C at outlets within one minute of running.

What records need to be kept for compliance?
Temperature logs, service reports, risk assessments, and flushing schedules.

Can Immersion heaters be tested without draining the cylinder?
Yes, electrical continuity and resistance can be tested without draining, but visual inspection may require access.

 

Partner with Backer Heatrod for Reliable Winter Readiness

Backer Heatrod is a trusted supplier of commercial water heating solutions, offering:

  • Replacement immersion elements and thermostats
  • Technical support for servicing and compliance
  • Fast delivery on essential components
  • Prepare your system for winter with confidence.

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