Strebel S-CBX 105, Руководство по установке, эксплуатации и техническому обслуживанию

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12.8 Demand for Domestic Hot Water
12.8.1 N
O
D
OMESTIC
H
OT
W
ATER
; DHW
MODE
0
No domestic hot water is available. The T_DHW_Out sensor does not need to be connected.
12.8.2 DHW S
TORAGE WITH SENSOR
; DHW
MODE
1
Mode 1: DHW is prepared by warming up a store. Either a DHW pump or 3-way valve can be used to switch to
DHW mode.
The DHW temperature in the tank is measured with sensor T_Store and set with parameter DHW_Store_Setpoint.
When this sensor drops below DHW_Store_Setpoint – DHW_Store_Hyst_Down the control detects a demand for
the store and starts the general and DHW pump.
If the supply temperature T_Supply is below DHW_Store_Setpoint + DHW_Store_Supply_Extra –
DHW_Supp_Hyst_Down the boiler is started as well.
When the boiler is ON the power is PID-modulated so T_Supply is regulated towards
DHW_Se DHW_Store_Supply_Extra.
The boiler is stopped when the supply temperature rises above
DHW_Store_Se DHW_Store_Supply DHW_Supp_Hyst_Up.
The demand for the tank is ended when the tank-sensor rises above
DHW_Store_Se DHW_Store_Hyst_Up. The pump continues DHW_Post_Pump_Period.
DHW Priority
Standard DHW demand has priority over CH demand but the priority period is limited up to
DHW_Max_Priority_Time. The priority timer starts when both CH and DHW demand are present. After the
DHW_Max_Priority_Time is achieved, the control will switch from DHW to CH operation. CH has priority now for
a maximum period of DHW_Max_Priority_Time.
Different DHW Priority types can be chosen:
DHW priority Description
0 = Time DHW has priority to CH during DHW_Max_Priority_Time
1 = OFF CH always has priority to DHW
2 = ON DHW always has priority to CH
Default DHW_Priority is set to 2.
Store warm hold function
Because of the presence of the indirect tank sensor ( T_Store ) the control can detect demand for holding the
indirect tank hot. If T_Store drops below DHW_Store_Setpoint - DHW_Store_Hold_Warm the boiler starts at
minimum power.
The boiler stops if T_Store is higher than DHW_Store_Se DHW_Store_Hyst_Up .
Relevant variables
Specific Parameters Level (Default) Value Range
DHW_Mode 2: Installer 5 0, 1, 2, 3, 5, 6, 7, 8
DHW_Store_Setpoint Sets the desired DHW temperature. 1: User 57 ºC (135 ºF) 40...71 ºC (104...160 ºF)
DHW_Store_Supply_Extra
Increases the supply temperature to the store until
DHW_Store_Setpoint + DHW_Store_Supply_Extra.
2: Installer 15 ºC (59 ºF) 0...30 ºC (0...86 ºF)
Status Variables Value
DHW control state
Central Heating controller state
0 = Idle
1 = Request
2 = Demand
3 = Post circulation
4 = Off