Bosch SSB1000 TL - Page 32

6720892984 (2019/02) US SSB
32 | Main control
Relevant variables
Specic Parameters Level
(Default) Value Settable
°C °F °C °F
DHW_Mode 2: Installer 0 0, 1, 2, 3, 5, 6, 7, 8
DHW_Store_Setpoint
Sets the desired DHW temperature.
[°C/°F] 1: User 57 135 40..71 104..160
DHW_Store_Hyst_Down
Hysterese to detect store demand. Condition: T_Store below DHW_Store_
Setpoint less DHW_Store_Hyst_Down.
[°C/°F] 3. Factory 5 9 0..20 0..36
DHW_Store_Hyst_Up
Hysterese to end store demand. Condition: T_Store above DHW_Store_
Setpoint + DHW_Store_Hyst_Up.
[°C/°F] 3. Factory 5 9 0..20 0..36
DHW_Store_Supply_Extra
Increases the supply temperature to the store until DHW_Store_Setpoint +
DHW_Store_Supply_Extra.
[°C/°F] 2: Installer 15 27 0..30 0..54
DHW_Priority [-] 2
0 ¨ Time
1 ¨ Off
2 ¨ On
3 ¨ Parallel
DHW_Supp_Hyst_Down
Hysterese to start burner for DHW. Condition: T_Supply below DHW_
Supply_Setpoint less DHW_Supp_Hyst_Down.
[°C/°F] 3. Factory 5 9 0..20 0..36
DHW_Supp_Hyst_Up
Hysterese to stop burner for DHW. Condition: T_Supply above DHW_
Supply_Setpoint plus DHW_Supp_Hyst_Up.
[°C/°F] 3. Factory 5 9 0..20 0..36
DHW_Store_Hold_Warm
If T_Store drops below DHW_Store_Setpoint the store warm hold function
becomes active.
[°C/°F] 3. Factory 5 9 0..10 0..18
Status variables Level
Value/Range
°C °F
DHW control state
Central heating controller state
0 ¨ Idle
1 ¨ Request
2 ¨ Demand
3 ¨ Post circulation
4 ¨ Off
5.2.2.3 DHW mode 2 – Storage with thermostat
In this Mode DHW is prepared by warming up a indirect tank. Either a DHW pump or 3-way valve can used to switch to DHW mode. The temperature of
the DHW in the indirect tank is regulated by a thermostat (instead of a sensor), which should provide only an open/closed signal to the control.
When the thermostat closes the control detects a demand for the tank and starts the DHW pump.
If the supply temperature
T_Supply drops below DHW_Store_Setpoint + DHW_Store_Supply_Extra – DHW_Supp_Hyst_Down the burner
starts.
When the burner is ON the power is PID-controlled based on
T_Supply toward DHW_Store_Setpoint + DHW_Store_Supply_Extra .
The burner is stopped when the supply temperature rises above
DHW_Store_Setpoint + DHW_Store_Supply_Extra + DHW_Supp_Hyst_Up .
The demand for the DHW is ended when the store thermostat opens. The pump continues
DHW_Post_Pump_Period after the DHW demand
stopped.
DHW priority
See paragraph “5.2.2.2 DHW mode 1 – Storage with sensor” pag. 31