Mitsubishi Electric Ecodan EHST20 serie Para El Instalador página 41

5
System Set Up
Forced dHW
The forced DHW function is used to force the system to operate in DHW mode. In
normal operation the water in the DHW tank will be heated either to the set tem-
perature or for the maximum DHW time, whichever occurs first. However should
there be a high demand for hot water 'Forced DHW' function can be used to pre-
vent the system from routinely switching to space heating and continue to provide
DHW tank heating.
Forced DHW operation is activated by pressing button F1 and Back button in the
'Option Screen'. After DHW operation finishes, the system will automatically re-
turn to normal operation. To cancel forced DHW operation hold down button F1 in
the 'Option Screen'.
Heating
The heating menu deals with space heating typically using either a radiator or
under-floor system depending on the installation.
From the main settings menu
1. Use F2 and F3 buttons to highlight heating icon then press CONFIRM.
2. The heating menu will be displayed.
3. To select the sub-menus press the function button below the icon required.
E.g. for mode change of Zone1 press F1
Heating
1. Under this sub-menu the mode of heating is selected.
2. Choose between
• Flow temperature ( )
• Room temperature ( )
• Compensation curve ( )
3. To choose between the different modes for heating, highlight the mode pre-
ferred and press select.
If compensation curve mode was selected as the heating mode please read the
following instructions.
explanation of compensation curve
During late spring and summer usually the demand for space heating is reduced.
To prevent the heat pump from producing excessive flow temperatures for the
primary circuit the compensation curve mode can be used to maximise efficiency
and reduce running costs.
The compensation curve is used to restrict the flow temperature of the primary
space heating circuit dependent on the outdoor ambient temperature. The FTC4
uses information from both an outdoor ambient temperature sensor and a tem-
perature sensor on the primary circuit supply to ensure the heat pump is not pro-
ducing excessive flow temperatures if the weather conditions do not require it.
<Compensation curve setting>
1. From the heating menu select edit using the F3 function button.
2. The compensation curve setting screen will be displayed.
3. In 2-zone heating operation, press F1 to switch between Zone1 and Zone2.
4. Press F2 to alter the Hi parameter (when flow temp is maximum and out-
door ambient temp is minimum).
5. Press F3 to alter the Lo parameter (when flow temp is minimum and out-
door ambient temp is maximum).
6. Press F4 to add an extra point (adjust).
Pressing F2-4 will cause the relevant edit screen to be displayed. Editing Lo and
Hi parameters is done in the same way; please see the following for more de-
tailed explanation of parameter editing.
In the parameter (Lo/Hi) edit screen the flow temperature and outdoor ambient
temperature for the compensation curve graph can be set and altered for the 2
extremes of Hi and Lo.
1. Press F1 and F2 to change the flow temperature (y-axis of compensation
curve).
2. Pressing F1 will raise the desired flow temperature for the set outdoor ambi-
ent temperature.
3. Pressing F2 will lower the desired flow temperature for the set outdoor am-
bient temperature.
4. Press F3 and F4 to change the outdoor ambient temperature (x-axis of
compensation curve).
5. Pressing F3 will lower the outdoor ambient temperature for the set flow tem-
perature.
6. Pressing F4 will raise the outdoor ambient temperature for the set flow tem-
perature.
40