Hello everyone,
I am working on a project in Europe where heat pumps are tested and certified in accordance with Eurovent criteria instead of AHRI 1230 as mentioned in ASHRAE 90.1 2010. In addition, we have noticed that Eurovent criteria might regularly change resulting to different heating and cooling efficiencies for exactly the same units as the test conditions change.
I have two questions:
1) Can we assume that Eurovent is equivalent to AHRI, therefore efficiencies tested as per Eurovent criteria are acceptable and therefore we meet the ASHRAE 90.1 minimum criteria as per chapter 6.4.1 as long as minimum efficiencies are met?
2) Assuming Eurovent is acceptable, how do we treat those units achieving different efficiencies from time to time (e.g. efficiency for cooling equals to 4.0 in 2020 and 2.7 in 2021)?
Thank you in advance.
Kind Regards,
Aris
Jean Marais
b.i.g. Bechtold DesignBuilder Expert832 thumbs up
July 13, 2021 - 9:31 am
Here we see a prime example of how bad "rating" efficiencies can be to determine performance. Thankfully, ASHRAE and LEED require us to model the equipment in the energy simulation which will model the machine at all the different performance points that occur in the 8760 timestep hours. If the performance matrix (or curves) are correctly modeled, the performance will be correctly reflected in the relative energy usage. The LEED reviewers should know this and therefore accept that the "rated" values are very subjective to the rating proceedure used. If you explain that the manufacturer does not supply american ratings, but that the rating efficiencies meet the minimum required by EU law, I think you'll be fine.
Aris Koliopoulos
Sustainability ConsultantDCarbon
July 13, 2021 - 10:14 am
Thanks for the response Jean.
Your appoach sounds reasonable. I agree that seasonal or part load efficiencies should be used anyway as they reflect the actual efficiencies.
Aris