Danfoss ECL 2000, User Manual

Page: 74 / 106

Service Settings
EY.65.H4.02
68
10.4.5 Override
The setting pictures under the Override menu item include parameters that determine
the priority of the service water heating, the operation of heat circuits during night
setback, safety thermostat settings for individual circuits and mixing difference.
Hot-water priority These settings determine how the controller should react if it is not possible to main-
tain the hot-water temperature at the setpoint specified by the user.
Display text Parameter Default value,
range Description
Priority Default value:
OFF
Range:
ON, OFF
When this parameter is set to ON, the
heating of water takes priority over the
heating of rooms
Max. devia-
tion Maximum
deviation Default value:
–5 K
Range:
–60-0 K
The number of degrees the hot-water
temperature or charging temperature is
allowed to drop below the setpoint be-
fore the priority function is activated.
1
When this happens, the motor valves to
the heat circuits are gradually closed
Flow temp.
diff. Flow tem-
perature dif-
ference Default value:
–20 K
Range:
–60-0 K
This parameter is active when Priority is
set to OFF, which means that the heat
circuit(s) and the hot-water circuit are
operated at the same time. An example is
illustrated in Figure 9 on page 69
In such a situation, the charging tem-
perature needed in the hot-water circuit
can be significantly above the calculated
flow temperature in the heat circuit. The
parameter Flow temp. diff. is used to
prevent the actual flow temperature in
the heat circuit from getting too high:
When Flow temp. diff. is exceeded, the
pump in the heat circuit is stopped
1 Whether it is the charging temperature or the hot-water temperature depends on the type of hot-water circuit.
More information about the hot-water priority of the various hot-water circuits is available in the ECL 2000
Technical Manual (ref. [3])