Hitachi RWM-(H)FSN3E, Service Manual

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5 Control system
SMGB0070 rev. 1 - 08/2011
145
5
Heater for emergency mode
When user allows emergency mode (DSW4-4 ON), heater may operate in said mode. This configuration
allows also Hot Sanitary Water emergency operation.
N O T E
For more information refer to chapter Optional functions.
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Boiler combination for space heating
Boiler operation
Boiler will only operate if unit is in Space Heating or Hot Sanitary Water modes. It will always be disabled in any other mode
(Swimming Pool and Cooling mode).
Unless otherwise stated, all procedures in this chapter will only affect operation when performing Space Heating. Boiler
operation during Hot Sanitary Water operation will be explained in its own sub-heading below.
Boiler
High temperature
(60 ºC)
Low temperature
(35 ºC)
Boiler
signal
Boiler will only operate when Heating Accessory is set to Boiler or Boiler. Boiler and Heater can never work at the
same time. The decision as to how to operate is based on ambient temperature and is explained in “Use Heater”
below.
System protection will always have priority over boiler operation wherever it applies.
User Variables:
CODE REF Description Default Value
5-000 HS Complementary Heating = (Only HP, Heater, Boiler, Boiler) Only HP
C A U T I O N
The boiler is configured as alternating with the heat pump. A hydraulic separator or buffer tank must be used
to ensure proper hydraulic balancing. Additional Water pump (WP3) and water sensor (Two3) are necessary for
boiler combination control.