4 Operation
User reference guide
24
EGSAH/X06+10DA9W(G)
Daikin Altherma 3 GEO
4P569819-1 – 2019.02
4.9
Weather-dependent curve
4.9.1
What is a weather-dependent curve?
Weather-dependent operation
The unit operates 'weather dependent' if the desired leaving water or
tank temperature is determined automatically by the outdoor
temperature. It therefore is connected to a temperature sensor on
the North wall of the building. If the outdoor temperature drops or
rises, the unit compensates instantly. Thus, the unit does not have to
wait for feedback by the thermostat to increase or decrease the
temperature of the leaving water or tank. Because it reacts more
quickly, it prevents high rises and drops of the indoor temperature
and water temperature at tap points.
Advantage
Weather-dependent operation reduces energy consumption.
Weather-dependent curve
To be able to compensate for differences in temperature, the unit
relies on its weather-dependent curve. This curve defines how much
the temperature of the tank or leaving water must be at different
outdoor temperatures. Because the slope of the curve depends on
local circumstances such as climate and the insulation of the house,
the curve can be adjusted by an installer or user.
Types of weather-dependent curve
There are two types of weather-dependent curves:
▪ 2-points curve
▪ Slope-offset curve
Which type of curve you use to make adjustments, depends on your
personal preference. See
"4.9.4 Using weather-dependent
Availability
The weather-dependent curve is available for:
▪ Main zone - Heating
▪ Main zone - Cooling
▪ Additional zone - Heating
▪ Additional zone - Cooling
▪ Tank
INFORMATION
To operate weather dependent, correctly configure the
setpoint of the main zone, additional zone or tank. See
"4.9.4 Using weather-dependent curves" on page 25
4.9.2
2-points curve
Define the weather-dependent curve with these two setpoints:
▪ Setpoint (X1, Y2)
▪ Setpoint (X2, Y1)
Example
Y1
Y2
X1
X2
a
Item
Description
a
Selected weather dependent zone:
▪
: Main zone or additional zone heating
▪
: Main zone or additional zone cooling
▪
: Domestic hot water
X1, X2
Examples of outdoor ambient temperature
Y1, Y2
Examples of desired tank temperature or leaving water
temperature. The icon corresponds to the heat emitter
for that zone:
▪
: Underfloor heating
▪
: Fan coil unit
▪
: Radiator
▪
: Domestic hot water tank
Possible actions on this screen
Go through the temperatures.
Change the temperature.
Go to the next temperature.
Confirm changes and proceed.
4.9.3
Slope-offset curve
Slope and offset
Define the weather-dependent curve by its slope and offset:
▪ Change the
slope
to differently increase or decrease the
temperature of the leaving water for different ambient
temperatures. For example, if leaving water temperature is in
general fine but at low ambient temperatures too cold, raise the
slope so that leaving water temperature is heated increasingly
more at decreasingly lower ambient temperatures.
▪ Change the
offset
to equally increase or decrease the
temperature of the leaving water for different ambient
temperatures. For example, if leaving water temperature is always
a bit too cold at different ambient temperatures, shift the offset up
to equally increase the leaving water temperature for all ambient
temperatures.
Examples
Weather-dependent curve when slope is selected:
X1
X2
c
d
e
Y1
Y2
Y3
Y4
a
b
Weather-dependent curve when offset is selected:
