Toshiba ESTIA HWS-1501CSHM3-E, Service Manual

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61
8-3.
Hydro Unit Control 2) Control at the time of heating heater operation
• Controlled Object: Backup heater, Booster heater
The backup heater control starts when 13 minutes has passed after the heating heat pump operation started.
The backup heater control increases, decreases, or maintains the number of heaters every 10 minutes (FC)
depending on the difference between the heating set temperature (TSC_F) and the heater outlet temperature
(THO). Note that when the heating set temperature (TSC_F) is reached, the unit stops energizing the heater.
The single-phase model of 3 kW has the backup heater 1 only.
The three-phase model of 6 kW has heater 1+2 of 6 kW.
Booster heater operation come only output signal. (Booster heater activate under heater only mode)
Related FC
2-3) Heater control at the time of defrosting
• Object to be controlled: Backup heater
When a defrosting operation starts during the heating heat
pump operation, the unit energizes a backup heater (3 kW)
according to the heater outlet temperature sensor (THO) and
the set temperature (TSC_F) as follows.
1) When the heater outlet temperature sensor (THO) drops to
the temperature of 2°C below the set temperature
Defrosting ends according to the usual heater control.
2-4) Forcible heater energization
To prevent freeze, the unit energizes or stops energizing a backup heater (3 kW) regardless of the unit status, not
operated or in operation.
• Object to be controlled: Backup heater
1) Energization start condition: TWO < 4 or TWI < 4 or THO < 4
2) Energization stop condition: TWO 5 and TWI 5 and THO 5
Defrosting ends according to the usual heater control.
2-5) No heater operation
According to the DP_SW11 setting, the unit switches the energize/ not energize for the hot water cylinder, backup
heater, and booster. For details, see 10-1.
(Caution)
All heater should be added to this Air to water system.
The system has been designed to operate with all electrical heaters energized.
Item Operation flow and applicable data, etc.
70
TSC_F-0
TSC_F-2
TSC_F+2
THO
E zone
D zone
C zone
B zone
A zone
Diff : 2K
Diff : 2K
Diff : 2K
Abnormality detection
Heater off
KEEP
Heater output down every
5, 10, 15, or 20 minutes
Heater output up every
10, 20, 30, or 40 minutes
Status Heater ON / OFF
Heater 1 Backup heater 3 kW = ON
Heater 2 Backup heater 9 kW = ON
Heater 3 Heater 2 + Booster heater
FC No. Setting item Default Setting available range
20 Hot water supply heat pump start temperature 38°C 20-45°C
21 Hot water supply heat pump stop temperature 45°C 40-50°C
33 Heater control of down time 1:10 min 0:5 min 2:15 min 3:20 min
34 Heater control of up time 0:10 min 1:20 min 2:30 min 3: 40 min
Heater off
Heater 1
Heater 1
TSC_F
TSC_F-
β
(
β
=2)
TSC_F- α ( α =4)
THO
Status Heater ON / OFF
Heater 1 Backup heater 3 kW = ON