Overview
ISO 19455-1:2019 - "Planning for functional performance testing for building commissioning - Part 1: Secondary hydronic pump, system and associated controls" defines a planning methodology for Functional Performance Testing (FPT) of secondary hydronic pumps and their controls in HVAC systems. Intended for use in the design phase of new buildings and retrofit projects, this standard clarifies what information is required, what operational data should be recorded, and how measured data is to be analysed - without prescribing concrete measurement techniques.
Keywords: ISO 19455-1:2019, functional performance testing, FPT, building commissioning, secondary hydronic pump, HVAC.
Key topics and technical requirements
- Scope & purpose: Establishes how to design building environmental systems to enable effective FPT and verification of design intent and energy-saving functions.
- Required information: Basis of design (BoD), design documents, drawings and product specifications to support commissioning and FPT planning.
- Data acquisition: Identifies required data (e.g., water flow rates, energy consumption or electrical current, inverter frequency, supply-side or pump pressure difference, and heat exchanged in air handling units). For new buildings, data can come from the Building Automation and Control System (BACS); retrofits may use temporary loggers. (See Annex A for data acquisition planning.)
- Pump control types: Defines multi-unit pump staging and rotation-speed control strategies:
- Type A (constant delivery pressure) - A1 (supply‑side pressure control) and A2 (pump pressure-difference control).
- Type B (variable delivery pressure) - B1/B2 variants tied to end-pressure difference.
- FPT methods: Structured test procedures and analysis steps for:
- Test 1 - relationship between water flow rate and number of operating pumps.
- Tests 2 & 3 - relationship between water flow rate and pressure.
- Test 4 - relationship between water flow rate and energy consumption.
Each test follows measurement, calculation, analysis, clarification of design specification and comparison to design values.
Applications
- Integration of commissioning requirements into the design documents and BoD.
- Verification of hydronic pump staging, control algorithms and actual energy performance after handover.
- Supporting energy-efficiency validation, troubleshooting of system behavior, and retrofit performance checks.
Who should use this standard
- Building designers, HVAC engineers and system integrators
- Commissioning providers and contractors
- Building owners/clients and facility managers
- Government officials and researchers involved in building performance and energy efficiency
Related standards
- ISO 16813 - Building environment design - General principles (defines commissioning context).
- ISO 16484-1 - Building automation and control systems - Project specification and implementation.
ISO 19455-1:2019 provides a practical, design-phase framework for planning FPT of secondary hydronic pump systems, helping stakeholders ensure reliable, energy-efficient HVAC operation through structured testing and data-driven verification.