District Heating Leakage Protection System FBU

system FBU-2.5-M2 Application:
Single-family homes

  • Kamstrup MULTICAL®603 Heat Meter
  • Extra Kamstrup ULTRAFLOW® Flow Meter
  • Cut-Off Valves
  • Check Valve for Return Pipe
  • Plug-In KMP Interface Module
  • FBU Controller with
    12 months' attachment to AERS
Ill.: system FBU-2.5-M2

Monitoring Functions

If the volume flow difference in two successive measuring periods of max. 210 seconds exceeds the set threshold, leakage alarm is issued for volume flow difference.

The patented ALOHA® mechanism allows air pockets to pass through the flow meter without causing false alarms, and without adversely affecting system sensitivity.
Systems FBU thus offers optimum reliability.

Seepage: (OptiTight®)
The patented OptiTight® mechanism executes one or more times daily, testing the tightness of the installation by individually controlling the cut-off valves, whereby even minute seepage is detected.
If seepage is detected, alarm is given, and the installation is cut off.

System Fault:
Whenever a valve is closed, the system checks its tightness. If a component fails, a System Fault alarm is given.
If an internal voltage supply fails, a System Fault alarm is given.
Functional errors reported from Kamstrup MULTICAL® cause a System fault alarm.
System Faults do not cause installation cut-off.

Alarm Functions

On leakage errors, System FBU cuts off the installation, gives audible and visible alarm indication and drops the alarm relay.
System faults are reported via relay as well as audibly and visibly if possible. Valve errors are indicated visibly.


Controls and Indicators:
Status, Data, and Alarm indicators, buzzer.
Key for alarm mute and acknowledge.

Leak Monitoring Volume:
Measuring period 210 sec.; truncated when threshold exceeded; alarm if repeatedly exceeded.
Threshold adjustable 0.5-1-2-5%Qp + 1-2-5-10%Qact.

Execution: 1, 2, 3 or 4x/day, or by external command.
Start at 02:00 + 24 / 2*12 / 3*8 or 4*6 hours.
Threshold 20-40-60-80%Qp, duration 5-10-20-40m.

Mains Connection:
230V 50Hz L/N/PE via key switch.
Power consumption max 20VA.


Liquid Sensor Attachment: (Opt. V)
accommodates one or two liquid sensors type LS-X for protection of sensitive areas with optional cut-off.

By attachment to AERS, System FBU may text any mobile phone on alarm.


Download System FBU data sheet in pdf format

Visit Kamstrup's theme page on leak monitoring