I would check the part load performance below 50% load and ensure you
are happy with what the default curves assume as I believe these
curves FSEC developed may extrapolate from >50% PLR manufacturer's
data. There is a question whether the units cycle or continue to turn
down, but in either case the curve we believe is not representative.
Very tough to get part load data from manufacturer's. Has anyone else
overcome the limitations of manufacturer's data. The efficiencies
promise a lot for small commercial and multi-unit residential
buildings yet we have relatively such poor base data ...
Regards,
Graham