EN 14511 Testing Guidance

For VEU Activity 44 and ESS IHEAB, EN 14511 testing forms the foundation of heat pump performance modelling.

While EN 14511 is a European standard, in the VEU & ESS schemes it is used for a different purpose: to construct a heat pump performance map that feeds into annual AS/NZS 4234 simulation models.

This performance map defines how the heat pump performs – thermal capacity, input power and COP – across combinations of air temperature (dry bulb/wet bulb) and water inlet temperature.

Selection of EN 14511 test conditions is not simple. Refrigerant choice, control logic and thermal storage configurations all impact the range of test conditions chosen.

Regulator Minimum Requirements

Scheme administrators (ESC, IPART) allow some flexibility in the selection of test conditions to suit different products. Scheme administrators minimum requirements are:

• Water temperatures: maximum inlet temperature during operation (i.e. 60°C)
• Air temperatures (dry bulb/wet bulb): 2°C/1°C, 7°C/6°C, 12°C/11°C or 19°C/15°C

The maximum inlet temperature is the highest inlet water temperature that would be expected during normal operation. Two examples:

• R-290 heat pump; tank set point 75°C; temperature rise (deltaT) 5K
  • Maximum inlet temperature = 70°C.
• CO2 heat pump; outlet 90°C; compressor turns off when inlet temperature exceeds 50°C
  • Maximum inlet temperature = 50°C.

Instead of a “low temperature operation penalty”, the results are linearly extrapolated down to dry bulb -5°C. It is therefore not necessary to test at -5°C dry bulb.

Additional Testing to Improve Modelling Outcomes

Inlet Water Temperatures

It is strongly recommended to include additional inlet water temperatures to capture maximum performance data:

• Add minimum inlet water temperature ~10°C to showcase high capacity & COP at low water temperature
• Add intermediate inlet water temperaure between minimum & maximum to capture shape of performance curve. Units tend to spend more operation time at higher temperatures, thus include bias towards the higher temperature range, for example, 50°C.

Air Temperatures

It is strongly recommended to add a higher dry bulb point (i.e. 30-38°C) to show the higher performance at higher air temperatures. System capacity & COP tends to be higher in hotter ambient conditions. While not mandatory, this additional test point provides signficant improvement on certificate outcomes.

Baseline Recommendations

Baseline EN 14511 testing recommendation for R-290 systems:

• Water temperature (inlet) = 10°C, 50°C, 70°C
• Air temperature (dry bulb/wet bulb) = 2°C/1°C, 7°C/6°C, 19°C/15°C, 38°C/25°C

Baseline EN 14511 testing recommendation for CO2 systems:

• Water temperature (inlet) = 10°C, 30°C, 50°C
• Air temperature (dry bulb/wet bulb) = 2°C/1°C, 7°C/6°C, 19°C/15°C, 38°C/25°C