Toshiba MMW-UP0271LQ-E Service Manual page 17

No. Item
6 Heater control 1. While the heating thermostat ON, the heater relay is output by difference between
Ts and TWI, and difference between Ts and TWO, Ts and TG.
2. In case of Ts > 45˚C, the heater relay is output as shown below by the difference
between Ts and TWO.
Ts – TWO
7 Water As the following description, the pump and heater are controlled based upon TC1, TCJ,
Heat exchanger TCJ2, TWO and TWI, regardless of Start/Stop operation.
frost prevention 1) Pump ON condition
(1) When any one of TC1, TCJ, TCJ2, TWO or TWI became below 5˚C
(2) When TC1 < 10˚C and TCJ - TC1 ≥ 5˚C
2) Pump OFF condition
When all of TC1, TCJ, TCJ2, TWO and TWI became above 12˚C
3) Heater ON condition
When TWI or TWO became below 15˚C after the pump was OFF and 65 seconds
progressed.
4) Heater OFF condition
TWI or TWO ≥ 15˚C continued for 2 minutes.
8 Cooling oil While the outdoor unit is recovering cooling oil (refrigerant), the hot water modules
(refrigerant) perform the following control tasks:
recovery control
1) Close the hot water module PMV to a certain degree.
2) Engage in recovery control for a specified period of time and return to stand by
at the end of this period upon completing the control.
3) Open the SV valve throughout the recovery control period.
9 Heating While the outdoor unit is recovering heating refrigerant (oil), the hot water modules
refrigerant (oil) perform the following control tasks:
recovery control
1) Open the indoor PMV to a certain degree.
2) Complete the recovery operation depending on the TWO.
The time to complete is determined by each indoor unit.
Heater ON condition: A and B as shown below Table 1 or Table 2
Heater OFF condition: A or B as shown below Table 1 or Table 2
(˚C)
P1
Q1
∗
Ts ≥ 46˚C
1.5
–0.5
Specification
Table 1
Ts – TWI
P1
Q1
Heater : ON
Table 2
Ts – TWO
Heater OFF
P1
Q1
Heater : ON
Heater OFF
– 17 –
TG: Satisfaction
Ts – TWO
(A) (B)
7˚C 2˚C
5˚C 0˚C
Ts – TG
(A) (B)
2˚C –11˚C
0˚C –14˚C
TC1: Gas Temperature
TCJ: Liquid
TCJ2: Liquid
• Recovery operation
normally takes place
roughly every 2 hours.
• Recovery operation
normally takes place
roughly every hour.
• The opening position
of the hot water
module PMV
depends on capacity
of the hot water
modules.
Remarks
temperature of
discharge
pressure
Temperature
Temperature