Hitachi RHUE-3AVHN, Руководство по обслуживанию

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Controller pack
Service Manual
86
DHW control functions
SMGB0066 rev.0 - 12/2009
dHW
Circuit
Heating
Circuit
dHW
Circuit
Heating
Circuit
DHW diverting valve system DHW pumped system
function •
The DHW function has priority over the Heating Circuit, which means that when the DHW storage tank is being loaded,
the heating circuit will be switched off.
The DHW function will be blocked (temporarily disabled) when the Tariff/Timer input is configured for DHW and the input
is open circuit (or alternatively short circuit as defined by parameter – see “DHW Time Program”).
Parameter Settings •
P1 System DHW Choice (default 0)
P1=0 No DHW function -
P1=1 System with DHW diverting valve -
P1=2 System with DHW pump -
4.4.2. dHW Control
function •
When DHW control is enabled, the system controller heats the DHW tank temperature to the DHW setpoint (P10). When
the DHW temperature drops below the DHW setpoint minus the DHW differential (P11), this function switches on the
DHW Pump or opens the DHW valve, and sets a supply setpoint equal to DHW se DHW supply offset (P12). The
DHW loading is complete when the DHW temperature rises above the DHW setpoint.
Supply Setpoint for DHW loading = DHW se DHW Supply Offset (P12)
DSET = DHW setpoint (P10)
SDHW = Supply Setpoint for DHW loading.
TDHW = DHW tank temperature
diagram •
DHW loading starts (power-on or DHW timer signal)
Supply water temperature set to P10+P12
(*)
DHW tank temperature (TDHW) rises above P10
DHW loading stops
Supply water temperature is determined by heating circuit
requirements.
DHW tank temperature (TDHW) falls below P10 - P11
DHW loading starts
Supply water temperature set to valve P10+P12
(*)

note
The Heat Pump outlet temperature setpoint will be equal -
to the Supply Water Temperature Se P31 (Heat
Pump supply offset) to account for pipe losses. The Heat
Pump outlet temperature setpoint is always limited to 55º
C or 50º C depending on the outside temperature.