M thermal Mono 
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Part 3 - Installation and Field Settings 
until at least t_INTERVAL_DHW minutes have elapsed.   
 
dT5_TBH_OFF  sets  the  temperature  difference  between  the  DHW  set  temperature  (T5S)  and  the  DHW  tank  water 
temperature  (T5)  below  which  the  immersion  is  not  used.  When  T5  >  Min(T5S+dT5_TBH_OFF,  65°C),  the  immersion 
heater is off. 
 
T4_TBH_ON sets the ambient temperature above which the immersion heater will not be used.   
 
t_TBH_DELAY sets the delay between the compressor starting and the immersion heater being turned on. 
 
T5S_DI sets the DHW tank disinfection operation target temperature. Caution: during the disinfection operation (duration: 
t_DI_MAX) the domestic hot water temperature at the hot water taps will at times be equal to the value set for T5S_DI. 
 
t_DI_HIGHTEMP sets that length of time that the DHW tank disinfection operation 
target temperature is maintained. 
 
t_DI_MAX sets the total duration of the DHW tank disinfect operation. 
 
t_DHWHP_RESTRICT  sets  the  maximum  length  of  time  that  the  heat  pump  will 
run in space heating or space cooling modes before switching to DHW mode, if a 
requirement for DHW mode exists. When running in space heating mode or space 
cooling mode, the heat pump becomes available for DHW mode either as soon as 
the space heating/cooling set temperatures have been reached (refer to Part 3, 7.5 “COOL MODE SETTING Menu” and Part 
3, 7.6 “HEAT MODE SETTING Menu”) or after t_DHWHP_MAX minutes have elapsed. 
 
t_DHWHP_MAX sets the maximum length of time that the heat pump will run  in DWH mode before switching to space 
heating  mode  or  space  cooling  mode  if  a  requirement  for  space  heating/cooling  modes  exists.  When  running  in  DHW 
mode, the heat pump becomes available for space heating/cooling either as soon as the DHW tank water temperature (T5) 
reaches the DHW set temperature (T5S) or after t_DHWHP_MAX minutes have elapsed. 
 
Figure 3-7.9 illustrates the effects of t_DHWHP_MAX and t_DHWHP_RESTRICT when DHW PRIORITY is enabled. The heat 
pump initially runs in DWH mode. After t_DHWHP_MAX minutes, T5 has not reached   
 
Figure 3-7.9: Operation in DHW PRIORITY 
Abbreviations: 
T5: DHW tank water temperature 
T5S: DHW set temperature 
T5stop: DHW mode leaving water temperature operating limit  
 
DHWPUMP  TIME  RUN  sets  whether  or  not  the  user  is  able  to  set  the  DHW  pump  (field  supply)  in  DHW  mode.  For 
installations with a DHW pump, select ON so that the user is able to set pump start times. 
PUMP RUNNING TIME  sets the length of time the  pump runs for  at each of  the user-specified start times on the DHW 
Figure 3-7.8: DHW tank disinfection   
Abbreviations: 
T5: DHW tank water temperature 
T5S: DHW set temperature