Slant/Fin VHG-100-CH, Installation And Service Manual

Page: 105 / 164

E93.1901EN032 Installation and Service Manual SlantFin VGH-CH / CO
105
Relevant variables
Specific Parameters Display
menu # Level (Default)
Value Range
DHW_Mode PB 1 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
PB 115 User 122
º
F
(50
º
C)
104
…
185
º
F (40
…
85
º
C)
DHW_Priority PB 42 Installer 2 0=Time, 1=OFF, 2=ON
DHW_Max_Priority_Time
Sets the maximum time for either DHW or
CH priority.
PB 43 Installer 60 min.
DHW_Post_Pump_Period PB 44 Installer 20 sec. 10...900
I
NSTANTANEOUS WATER HEATING WITH PLATE HEAT EXCHANGER
; DHW
MODE
5
This is the only mode available for Combi boilers (VGH-CO).
The other DHW modes are not available for Combi boilers.
In DHW mode 5 the water flow through a plate heat exchanger is checked with a DHW-out sensor and a rotary
switch. In this DHW mode the DHW-sensor is used for modulating the burner to the required DHW setpoint. The
rotary switch is used for detecting tap demand and detecting whether the burner can stay ON.
Specific Parameters Display
menu # Level (Default)
Value Range
DHW_Mode PB 1 Installer 0 for CH
5 for CO 0, 1, 2,3, 4, 5, 6, 7, 8
DHW_Setpoint
Sets the desired DHW temperature
PB 48 User 122
º
F
(50
º
C)
86
…
176
º
F
(30
…
80
º
C)
A
NTI
-
LEGIONELLA PROTECTION
This option is only available for Heating Only boilers (VGH-CH).
Anti-Legionella is enabled for CH-boilers for the DHW mode with an external tank with a sensor (DHW Mode 1).
To prevent legionella a special function is implemented in the software.
When DHW Mode 1 is selected the Anti-Legionella protection will be checked on the T_DHW_Out sensor. At least
once every 168 hours (7 days) the Anti_Legionella_Sensor must reach a temperature above
Anti_Legionella_Setpoint for a time specified by Anti_Legionella_Burn_Time.
If 7 days have passed and these conditions are not met, the boiler is forced to heat-up the system for Anti-Legionella.
When the Anti_Legionella_Sensor temperature is below Anti_Legionella_Setpoint the control switches ON the
circulators, when the Anti_Legionella_Sensor temperature is above Anti_Legionella_Setpoint plus 9 °F (plus 5 °C)
the control stops the circulators.
When DHW Mode 1 has been selected, the setpoint of the boiler will be at Anti_Legionella_Setpoint plus
DHW_Store_Supply_Extra.
If the supply temperature drops below the Boiler_Setpoint the boiler is started as well. The boiler is PID controlled
towards the Boiler_Setpoint. When the supply temperature rises above the boiler setpoint plus the
DHW_Supp_Hysterese_Up the boiler is switched OFF.
Every time an Anti-Legionella demand has ended the Anti_Legionella_Active_Counter is incremented to indicate
how many Anti- Legionella actions have been performed. Also, the Anti_Legionella_Wait _ime is started in order to
delay the next Anti-Legionella cycle.
The anti-legionella demand has priority over any DHW and CH demand. However, when the anti-legionella
protection is active and there is no heat or burn demand because the Anti_Legionella_Sensor is already at a high
enough temperature CH/DHW demand will be accepted as normal.
Parameters are factory set.
Parameter Factory Setting.
Anti_Legionella_Setpoint
Setpoint for Anti-Legionella demand
140
º
F (60
º
C)
Anti_Legionella_Burn_Time 30 Min.
Anti_Legionella_Wait_Time
Wait time for Anti-Legionella demand
120 min after cold start, 168 h after first successful
Anti-Legionella demand
Table 11.19
Table 11.20
Table 11.21