Toshiba HWT-602S21SM3W-E(TR) Service Manual page 75

Item
7-2. 6) Simultaneous operations of "hot water supply" and "cooling"
Operation Mode
* The heat pump runs for the hot water supply side when TTW is less than 38°C.
and Control
The heat pump maintains a supply of hot water for up to 30 minutes during a simultaneous operation.
Method
TTW < 38°C
The operation mode returns to normal when TTW become 52°C or more (DN_21).
7) Boiler control
The boiler assists the heating operation.
7-1) Boiler setting
• Connect its connection cable to CN22 port on the PC board of the hydro unit.
• DN_6B0 = "0/1" switches "Not using boiler (Default) / Using boiler".
Set the DN_6B0 to "1" when using the boiler.
• The temperature switching the boiler and heat pump: DN_23 = -10°C (Default) See the next item.
The boiler output becomes effective when the outside air temperature is -10°C or less.
• The boiler runs in heating operation. Also, the boiler runs when the heat pump is running for heating while heating
and supplying hot water simultaneously.
• Priority setting between the boiler and hydro unit: DN_3E = "0/1" switches the running priority; hydro unit (Default)
/boiler.
When DN_3E is set to "0" (Default), the hydro unit has priority, the boiler stops as inlet water temperature reaches
the hydro unit's temperature setting.
When DN_3E is set to "1", the boiler continues to run even after inlet water temperature reaches the hydro unit's
temperature setting. (The setting of DN_3E is effective during the HP+Boiler operation.)
• Coordination setting of the boiler and heat pump: when DN_5B = "0", the boiler and heat pump runs simultaneously.
When DN_5B = "1", only the boiler runs, pump ON. (However, if the external air temperature becomes the boiler-
HP switching temperature or more within 60 minutes)
When DN_5B = "2", the heater runs. (the heater may run instead for up to 60 minutes.)
When DN_5B = "3", only the boiler runs. (Pump OFF: Default)
DN_6B5 should be "0 (Default)"
<Installation example>
Outdoor
unit
Outdoor
unit
* Boiler & HP switching temp setting DN_23 = -10
** Boiler control / functionality setting DN_5B = 0 (HP+Boiler)
Operation flow and applicable data, etc.
Hot water supply side
Heat pump
Boiler
Boiler
Hydro unit
Buffer tank
Hydro unit
Buffer tank
Cooling side
stop
HEATING
HOT WATER
Radiator
HEATING & HOT
WATER
Radiator
COOLING
COOLING & HOT
WATER
74
TO <= -10* -10* < TO
Boiler + HP** HP
HP HP
Boiler for heating
HP for hot water HP
or heating
– HP (TO ≥ 10)
HP for cooling or HP for cooling or hot
hot water water