Function
WE
Configuration
Operating hours counter
OFF
0 h
Co1, Co2* -> Fb02 = ON
Initial value / Configurable as required
count
Counting the operating hours
rESEt
Reset operating hours to initial value
* Only in systems Anl 4 to 7
5.7
Boiler pump control
The boiler pump control is connected with the boiler control loop.
When a boiler is switched on to the first stage, the associated boiler pump is also switched on.
When the boiler is switched off, the boiler is switched off too either after the
Pump lag time has
elapsed or when the temperature falls below
Boiler flow limit.
In summer mode, the boiler pump is switched off together with the boiler when the deactivation
criteria are fulfilled.
In systems without hydraulic separator, in which the heating water must be circulated through
the boiler, the boiler pump may not be switched off. For this purpose, the
Continuous running of
pump
function is activated. The boiler pump continues to run when the lead boiler is switched
off and the valve is opened. As a result, the cold system water can reach the boiler return flow
pipe. If the return flow temperature is a factor that needs to be monitored in the boiler, the instal-
lation of an hydraulic separator is recommended.
Function
WE
Configuration
Continuous running of pump
OFF
5 min
55 °C
Co5 -> Fb14 = ON
Pump lag time / 0 to 90 min
Boiler flow limit / 20 to 120 °C
5.8
Boiler sensor acting as a thermostat
The boiler sensors KF1 and KF2 control the safety deactivation (–> section 8.10), which is trig-
gered whenever the maximum flow temperature is exceeded, as well as the temperature-de-
pendent pump lag of the boiler pumps Pu1 and Pu2 (–> section 5.7).
The maximum permissible flow temperature can also be monitored in systems Anl 4, 5 and 6
with thermostats. The inputs of the boiler sensors must be defined as binary inputs for this pur-
pose. The thermostats are connected to the same terminals as the boiler sensors.
EB 5474 EN
39
Boiler functions
