Hitachi RHUE-3AVHN, Руководство по обслуживанию

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85
DHW control functions
SMGB0066 rev.0 - 12/2009
Controller pack
Service Manual
4
4.3.4. Heating Circuit (Secondary) Pump
function •
When the heating circuit is enabled, the secondary pump will be switched on. When the heating circuit is disabled, the
secondary pump is switched off after a pump overrun time.
If the screed function is activated or system frost protection is active, the secondary pump continues to run.
If the system uses a DHW diverting valve and DHW storage tank loading is active, then the secondary pump continues to
run, since it is also used for the DHW loading.
Parameter Settings •
P2 Secondary Pump Selection (default 0 – no secondary pump)
P3 Pump Overrun Time (default 2 min)
Configuration Specific •
CONF 1,2: If a buffer tank or hydraulic separator is used between the Heat Pump and the heating circuit, it is
necessary to set parameter P2=1 to enable control of the secondary pump.
CONF 3,4,5: Secondary pump control is always enabled.
CONF 4,5:
If the mixed circuit maximum temperature limit is active, then the secondary pump is switched off.
4.3.5. Automatic no-load function
function •
When the calculated supply temperature setpoint (from OTC heating curve + room setpoint shift + room compensation
shift) is less than the room temperature, then the heating circuit can be switched off to save energy. A switching
differential of +/- 1K is applied.
Algorithm •
OTC supply setpoint < room temperature (TR1) – 1K => No-Load condition is active
OTC supply setpoint > room temperature (TR1) + 1K => No-Load condition is not active.
When the No-Load condition is active, the heating circuit is switched off.
Parameter Settings •
P30 No-Load Function enable/disable (default 1)
= 0 disabled
= 1 enabled
4.4. dHW ConTrol fUnCTIonS
4.4.1. dHW Storage Tank loading
Configuration Specific •
The DHW control function is available for configurations CONF1,2,3, and 5.
Enable/disable •
To enable DHW control, parameter P1 should be set according to whether the system uses a diverting valve or separate
pump for the DHW circuit.