Daikin Altherma User Reference Manual page 18

4 Operation
c Desired leaving water temperature when the outdoor
temperature equals or drops below the low ambient
temperature. Note: in heating, this value should be higher
than (d) as for low outdoor temperatures warmer water is
required.
d Desired leaving water temperature when the outdoor
temperature equals or rises above the high ambient
temperature. Note: in heating, this value should be lower
than (c) as for high outdoor temperatures less warm water
is required.
User reference guide
18
EGSQH10S18AA9W
Daikin Altherma ground source heat pump
4P351749-1D – 2016.09