Friedrich MW12C1H Detection of temperature sensor malfunction, Frequency Control, minutes Standby

Function and Control

6.3 Detection of temperature sensor malfunction

Detect malfunctions of temperature sensor any time.

In defrosting period, the temperature sensor malfunction will not be detected. 5 min after finishing defrosting, the system begins to detect the temperature sensor malfunction. In other times, the temperature sensor malfunction will be detected.

1. When short-circuit occurs to the temperature sensor for 30s:

The temperature sensor overheats. In this case, the complete unit will stop for protection. At the same time, the temperature protection and temperature sensor malfunction will be shown.

2. When break-circuit occurs to the temperature sensor for 30s:

The unit will stop and the temperature sensor malfunction will be displayed

6.4 Frequency Control

<Outline>

When starting the compressor, or when conditions are varied due to the change of the room, the frequency must be initialized according to the D value of the indoor unit and the Q value of the indoor unit.

Q value: Indoor unit output determined from indoor unit volume, air flow rate and other factors.

1. Pcontrol

Calculate D value in each sampling time (20 seconds), and adjust the frequency according to its difference from the frequency previously calculated.

2. Icontrol

If the operating frequency is not change more than a certain fixed time, adjust the frequency up and down according to the D value, obtaining the fixed D value.

When the	D value is small...lower the frequency.
When the	D value is large...increase the frequency.

3. Frequency management when other controls are functioning

When frequency is drooping;

Frequency management is carried out only when the frequency droops.

For limiting lower limit

Frequency management is carried out only when the frequency rises.

4. Upper and lower limit of frequency by PI control

The frequency upper and lower limits are set depending on indoor unit.

When low noise commands come from the indoor unit or when outdoor unit low noise or quiet commands come from indoor unit, the upper limit frequency must be lowered than the usual setting.

6.5 3-minutes Standby

Prohibit to turn ON the compressor for 3 minutes after turning it off.(except when defrosting)

6.6 Compressor Protection Function

When turning the compressor from OFF to ON, the upper limit of frequency must be set as follows. (The function must not be used when defrosting.)

		FREQUENCY
FCG 3	88
		FCG3
FCG 2	64
		FCG2
FCG 1	48
		FCG1
TCG1	240
TCG2	360
TCG3	180

TCG 1SEC

TCG 2SEC

TCG 3SEC

TIME

32