Toshiba RAS-10YAV-E, RAS-13YKV-E Heating Operation, Basic control, Starting and in stability

8-2-3. Heating Operation

Transferring of heating operation signal from indoor unit to outdoor unit starts.

The indoor fan motor operates by the room tempera- ture when selecting “AUTO” of “FAN” as shown in Fig. 8-2-6, and operates with a set air flow when selecting “Low” to “High”.

However, to prevent cold draft, revolution speed of the fan is restricted by indoor heat exchanger when air flow is AUTO (Fig. 8-2-7) and starting of FAN Manual.

[Basic control]

Set	0		LOW
temp.	–0,5
	–1	* 1
–	–1,5
(Roomtemp.) temp.)(Set	–2		* 2
			M+

[In starting and in stability]

	In starting	In stability
	• Until 12 minutes	• When 12 to 25
	passed after	minutes passed
	operation start	after operation start
FAN	• When 12 to 25	and room temp. is
		higher than (set
	minutes passed
AUTO
		temp. –3°C)
	after operation start
	and room temp. is	• When 25 minutes or
	3°C or lower than	more passed after
	set temp.	operation start
FAN	• Room temp. < Set	• Room temp. ≥ Set
Manual	temp. –4°C	temp. –3,5°C

The outdoor unit controls the outdoor fan based upon the operation signal sent from the indoor unit, and also controls revolution speed of the compres- sor motor.

–5,0

–5,5

[FAN AUTO]

HIGH

The power coupler (IC20) for four-way valve is turned on, and turned off in defrost operation.

(1) Heating capacity control

Calculate the difference between temperature

*1, *2 : Approximate revolution speed of M+ and L to linear according to temperature.

Fig. 8-2-6 Setting of air flow

[Cold draft preventing control]

The upper limit of fan revolution speed is shown below.

detected by room temp. sensor every minute and

the set temp. set on “Temp. indicator” and

variation amount of room temp.

Then, obtain the correction amount of the

command signal, and correct the current fre-

quency command signal.

(2) High-temp. release control

If temperature of the indoor heat exchanger

detected by the indoor heat exchanger sensor is

44	33
43	32
31	20
30	19
A + 4	A*2
A – 8	A – 8
FAN	Starting
	of FAN
AUTO
	Manual

HIGH

Approximate revolution speed of HIGH and SUL linear by Tc.

SUL*3

SUL ( NOTE : *1)

Stop

55°C or higher, compressor motor speed is

gradually lowered to prevent over-temp. rising of

compressed pressure.

If temperature becomes below 48°C, return to

above item (1).

(3) Current release control

The input current of compressor and outdoor fan

motor (Precisely inverter main circuit control

section) which occupy most of air conditioner

input is detected by the outdoor current sensor.

The compressor motor speed is lowered gradu-

ally according to the range of TO (outside air

Fig. 8-2-7 Cold draft preventing control

NOTES :

(1)Stops for 2 minutes after thermostat-OFF.

(2)24°C when the set temp. is 24°C or more Set temp. when the set temp. is below 24°C

(3)SUL : Super ultra low

temp.) if the input current exceeds the current

value determined in each zone as shown in Fig.

8-2-8 so that the input current does not exceed

the set value.

In case that the current lowered by approx. 0,5A

than each set value, return to above item (1).

– 30 –