Mitsubishi Electric s-MEXT-G00 006, Техническое руководство

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TM_s-MEXT_ME28relC_00_12_19_EN
Technical manual
TRANSLATION OF THE ORIGINAL INSTRUCTIONS 78
6 HEATING
6.1 ON/OFF HEATING ELEMENT MANAGEMENT
The parameter indicating the presence of on/off electric heaters is in the
“Optional” menu , which can be accessed by entering the “Service” password
The heating elements, when present, are given by two loads having different power; they are, therefore, always managed according to three heat steps, as shown below.
T
ambient
(°C)
P20.19 Differential
Step 1
Step 2
P50.02
P50.02 +
1/3
P20.19
P50.02 +
2/3
P20.19
Step 3
Figure 6-1: Heat resources management graph
The heat setting parameter is under the
“Set point” menu .
The heat Differential parameter is under the “Regulations” menu , which can be accessed by entering the “Service” password .
For the default values, see the parameters table.
The association of the h eaters with the steps reflects the “binary management”:
•
Step 1 : Heaters 1
•
Step 2 : Heaters 2
•
Step 3 : Heaters 1 + Heaters 2
Activating the heating elements is possible only when all the following conditions are met:
1. Adjustment consent is active.
2. The heating element overheating alarm is not present (from thermostat).
3. None of the compressors are in cooling mode.
6.2 POST-VENTILATION FUNCTION FOR THE ELECTRIC HEATERS
This function, available for all the units equipped with electric heaters, is for cooling the electric heaters when the unit is turned off and the electric heaters are still active.
When the OFF command is given (at the keyboard, by the supervisor, or remotely), the fan continues to run at nominal speed for a period of time set in the parameter
(P23.61).
The diagram below illustrates the function described above.
T(s)
P23.62 Heaters post-ventilation time
On
Off
Unit Status
Off
MIN Speed
P23.01
EC fan
Off
On
Electric heaters
Electric heaters post-ventilation
function enabled (P23.61)
Normal operation
Figure 6-2 : The chart illustrates the Post-Ventilation function for the electric heaters.
During the post-ventilation cycle, the icons of the electric heaters and fans flash on the main mask.
The parameters for enabling and configuring the Post-Ventilation function are in the
"Fan" menu , which can be accessed by entering the "Service" password .
For the default values, see the parameters table.