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

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12.8.3 DHW S
TORAGE WITH THERMOSTAT
; DHW
MODE
2
In this mode DHW is prepared by warming up an indirect tank. Either a DHW pump or 3-way valve can be 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 from the DHW indirect tank and starts the DHW pump.
If the supply temperature T_Supply drops below DHW_Store_Setpoint – DHW_Supp_Hyst_Down the boiler starts.
When the boiler is ON the power is PID-controlled based on T_Supply toward DHW_Store_Setpoint.
The boiler is stopped when the supply temperature rises above DHW_Store_Se DHW_Supp_Hyst_Up.
The demand for DHW ends when the indirect tank thermostat opens. The pump continues
DHW_Post_Pump_Period after the DHW demand has stopped.
DHW priority
See chapter 12.8.2 – DHW Mode 1 – Storage with sensor
Relevant variables
Specific Parameters Level (Default) Value Range
DHW_Mode 2: Installer 0 0, 1, 2,3, 4, 5, 6, 7, 8
DHW_Store_Setpoint
Sets the supply temperature from the boiler to
prepare DHW in the indirect tank
2: User 57 ºC (135 ºF) 40…85 ºC
(104…185 ºF)
DHW_Priority [-] 2 0=Time, 1=OFF, 2=ON
DHW_Max_Priority_Time
Sets the maximum time for either DHW or CH priority.
2: Installer 60 min.
DHW_Post_Pump_Period 2: Installer 120 sec. 10...900
12.8.4 I
NSTANTANEOUS WATER HEATING WITH PLATED HEAT EXCHANGER
; DHW
MODE
3
In DHW mode 3 the water flow through a plated heat exchanger is checked with a flow switch. If the switch
closes a water flow is detected, and either a DHW pump or a 3-way valve can be used to switch to DHW mode.
The temperature of the DHW is set with
DHW_Setpoint
.
If the T_DHW_Out sensor drops below DHW_Setpoint – DHW_Hyst_Down the burner starts. When the burner is
on, the power is PID-controlled based on T_DHW_Out toward DHW_Setpoint . The burner stops when the
T_DHW_Out temperature rises above DHW_Setpoint + DHW_Hyst_Up . When the flow switch opens the
demand for the tapping is ended and the burner stops. The pump continues DHW_Post_Pump_Period.
Based on a DHW temperature rise of 50 °C (90 °F) following minimum and maximum DHW flows are advised:
Boiler model Minimum flow (litre/ min) Maximum flow (litre/ min)
S-CBX 85 4.4 23.5
S-CBX 105 5.3 27.9
S-CBX 125 6.8 34.3
S-CBX 155 10.0 41.7
Specific Parameters Level (Default) Value Range
DHW_Mode 2: Installer 0 0, 1, 2,3, 4, 5, 6, 7, 8
DHW_Setpoint
Sets the desired DHW temperature
2: User 50 ºC (122 ºF) 30…80 ºC
(86…176 ºF)
DHW_Post_Pump_Period 2: Installer 20 s 10…900 s