Guide to Seasonal Commissioning

A Guide to Seasonal Commissioning After Handover

 

Seasonal commissioning, as recommended by industry standards such as CIBSE Commissioning Codes and BSRIA guidelines, is an essential process that ensures the building systems operate effectively and efficiently across varying seasonal conditions. It involves testing, fine-tuning, and optimizing systems after initial handover to address potential issues and adapt to real-world operational demands.

 

Why Seasonal Commissioning is Important

 

Seasonal Variations Impact Building Performance

Buildings experience different operational challenges in winter and summer due to variations in external temperatures, solar gain, and heating or cooling loads. Seasonal commissioning allows systems to be tested under these varying conditions to ensure they perform as intended.

 

Industry Recommendations

Both CIBSE and BSRIA recommend seasonal commissioning to verify that systems meet design intent throughout the year.

• CIBSE Commissioning Code M emphasizes ongoing performance verification and adjustments to achieve energy-efficient operation.
• BSRIA Soft Landings Framework highlights the importance of monitoring and optimizing systems during the early operational period to improve building performance.

Fine-Tuning Systems

Seasonal commissioning provides an opportunity to fine-tune control strategies, schedules, and setpoints based on actual building usage patterns and occupant feedback.

• For example, HVAC systems may require adjustments to heating setpoints, cooling capacities, temperature dissipation, or free-cooling strategies to align with seasonal demands.
• Fine-tuning helps eliminate inefficiencies, minimize energy consumption, and improve comfort levels for occupants.

 

What Fine-Tuning Achieves

 

Optimized Energy Efficiency

Small adjustments to schedules, temperature setpoints, and equipment modulation can significantly reduce energy use while maintaining comfort.

Improved System Stability

Fine-tuning ensures systems respond accurately to real-world conditions, reducing wear and tear on equipment and preventing frequent cycling of components like boilers, chillers, and pumps.

 

Enhanced Occupant Comfort

By addressing seasonal discrepancies, fine-tuning resolves comfort complaints, such as uneven heating in winter or insufficient cooling in summer.

 

Why Seasonal Commissioning Should Be Done During the Defects and Warranty Period

 

Opportunity to Address Issues Without Additional Cost:

The defects and warranty period provides a contractual window during which the building owner can request adjustments or rectifications from the contractor at no extra charge. Seasonal commissioning ensures any latent issues, such as underperforming systems or improperly calibrated controls, are identified and resolved early.

 

Validation of System Performance:

Seasonal commissioning allows the building owner to validate that the installed systems meet the design intent and comply with performance guarantees provided by the contractor.

 

Protection Against Long-Term Issues:

Identifying and addressing potential defects during the warranty period prevents more costly repairs or operational inefficiencies later.

 

Steps in Seasonal Commissioning

Pre-Commissioning Planning:

• Schedule commissioning activities to coincide with seasonal transitions (e.g., autumn for winter testing, spring for summer testing).
• Review design documentation, as-built drawings, and the original commissioning report to establish performance baselines.

System Testing and Verification:

• Test HVAC systems, including boilers, chillers, heat pumps, and associated controls, under seasonal conditions.
• Verify temperature setpoints, pressure readings, and flow rates across critical components like VT circuits, radiators, and air handling units (AHUs).
• Confirm system response to external factors, such as free cooling during mild conditions or full heating demand on cold days.

 

Fine-Tuning Adjustments:

• Optimize control schedules to match actual building usage patterns.
• Adjust setpoints for heating, cooling, and ventilation to balance comfort and efficiency.
• Monitor and refine sequences of operations, such as boiler lead-lag or pump modulation, to ensure stability and energy savings.

 

Occupant Feedback and Monitoring:

• Gather feedback from building users to identify comfort or operational issues.
• Use BEMS data to analyze system performance trends and make informed adjustments.

 

Documentation and Reporting:

• Provide updated commissioning reports, including revised settings and operational recommendations.
• Ensure these documents are added to the O&M manual for future reference.

 

Key Benefits of Seasonal Commissioning

 

• Energy Savings: By aligning system performance with seasonal demands, energy waste is minimized.
• Extended Equipment Lifespan: Fine-tuning prevents equipment from operating inefficiently, reducing wear and tear.
• Improved Comfort and Productivity: Occupants benefit from a more stable and comfortable environment throughout the year.
• Warranty Compliance: Issues identified and resolved within the defects period help ensure long-term reliability without additional costs.

 

By incorporating seasonal commissioning as part of the handover process, building owners can ensure their systems perform optimally, meet design expectations, and provide comfort and efficiency year-round. This proactive approach ultimately leads to a smoother operational lifecycle and fewer post-occupancy complaints.