Eco-King HWB-299, Installation And Service Manual

Page: 97 / 124

E93.1801EN171 HWB installation manual 97
Cascade Error handling
16.4.1 C
ASCADE
F
ROST PROTECTION
Frost protection on a cascade is active on two levels
1. Frost protection for burner cascade
The ‘frost protection’ function for a burner cascade is related to the water heater sensor temperatures.
When the supply / Inlet temperatures of the managing water heater are below:
Cascade_Frost_ Protection:
The cascade CH/system pump and the general pump of the managing
boiler start running.
Cascade_Frost_Protection minus 9
°
F
(minus 5 °C)
Cascade heat demand is activated; the general pumps of all the cascaded
boilers will be started.
Demand with setpoint Cascade_Frost_Protection allows the boilers to
start burning until the Inlet temperature of the managing boiler is above
Cascade_Frost_Protection plus 9 °F ( plus 5 °C).
2. Frost protection on boiler
As last protection the controllers for the boilers can force themselves to burn.
If the boiler supply/Inlet temperature drops below 41 °F (5 °C) the boiler starts at minimum power and continues
burning until the lowest of both supply and Inlet temperatures are above 59 °F (15 °C).
Specific Parameters Level (Default) Value Range
Cascade frost protection
Temperature for frost protection
2: Installer 59 ºF (15 ºC) 50...86 ºF (10...30 ºC)
16.4.1 E
MERGENCY MODE
Managing boiler error
When the managing boiler is in error mode, the depending boilers can go into the "Emergency_Mode", if enabled.
In emergency mode the system setpoint is set to the temperature of the Emergency_Setpoint and all cascaded
boilers start burning on this setpoint.
NOTE: the default setting is 122 °F (50 °C)! Make sure the right temperature is set.
Specific Parameters Level (Default) Value Range Parameter
Permit Emergency Mode
Installer Yes Yes/No Module Cascade parameter 72
Emergency Setpoint Installer 122 ºF (50 ºC) 68 - 194 °F (20 - 90 °C) Module Cascade parameter 75
Dair active Installer Yes Yes/No Boiler parameter 139
For proper functioning of this emergency mode, the following settings are necessary in the managing boiler (in-
staller password required):
- Module Cascade parameter no. 72: "Permit_Emergency_Mode" has to be set on "yes".
- Module Cascade parameter no. 75: "Emergency_Setpoint" has to be set on the right temperature.
- Boiler parameter no. 139: "Dair active" has to be set on "No".
NOTE: do not de-activate the Dair function before commissioning the system and adjusting the boilers!
When the managing unit is reset from lockout state, the cascade controllers are re-initialized.
16.4.2 L
OSS OF CASCADE COMMUNICATION
The burner controller of the managing boiler is aware of how many dependents should be present in the system.
The total number of boilers is stored in the BCU (parameter 147). When powering on the system the leading boiler
has to detect all depending boilers within 60 seconds.
When not, all dependent boilers are detected the control will show the CC_Loss_Communication warning. When
the communication with any of the depending boilers is lost during operation, the control will show the
CC_Loss_Communication warning after 60 seconds, which is purely informative and will not block the control.
Table 15-1