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Multiple boilers, heating and hot water using a low loss header with
the iSense Pro controller (Optimising/weather compensated control
for dual heating zone and hot water from all or single boilers)
Power Supply
• Boilers require a permanent 230v single phase supply fused at 6.3 amps connected to the
factory fitted fly lead.
Boiler Interlocks
(for pressure switches etc.)
• Safety Interlock - remove the existing link and fit volt free switch pair to BL on the main
control PCB. If the circuit is open the boiler will go to a shut down mode displaying code
9 and will restart when the circuit is closed
Indication Controls
(to report actual function)
• Common Alarm - volt free relay on SCU-X01 (see boiler manual for full details)
• Boiler Run - volt free relay on SCU-X01 (see boiler manual for full details)
Boiler Control Settings
(see 5.7.2 in technical documentation)
• Set boiler codes P1 to the required flow temp i.e. 80 = 80ºC (system design requirements)
• Boiler will recognise the type of control setting used
Fitting the controls
• Use the following hydraulic and wiring diagrams to best match the building requirements
• Fit the iSense Pro in the supplied wall mounted box adjacent to the boiler plant
• Connect all chosen auxiliary controls i.e. pumps, 3 way valves, outside sensor, flow sensors
etc. as indicated
Control Logic
• Set up the iSense Pro controller in conjunction with the iSense Pro installation and service
manual and to suit the installation and building heat loss response time. It will provide timed
weather compensated heating with an optimum start facility (uses inside and outside
sensors to delay the on time as dictated by weather conditions)
• Heating (all boilers available): during the timed on periods the heating will be daytime
weather compensated (in accordance with the heating curve programmed). The controller
will directly control each boiler, modulating their output and calling as many as are required
to achieve the desired comfort conditions dictated by the compensation parameters
• Hot water: two hydraulic options are available as shown in the diagrams. When using
the single boiler option, the hot water controls, i.e. the pump and sensor, are taken to
the boiler controls. A separate volt free time control will have to be used (not supplied
by Remeha Commercial)
• The following diagrams QP009 to QP009E show systems with two zones.
If only using a single zone, use zone B controls and omit zone C controls
Kit KT1154 will enable the iSense Pro controller to operate as a boiler sequencer. This will
require a 0 - 10v input from an external source i.e. BMS controller. The iSense Pro will control
the boilers to achieve the setpoint temperature supplied from the BMS control i.e. 5v will equal
50ºC. How the iSense Pro will sequence the boilers (lead/lag etc) will depend on how the user
control parameters are set within the iSense Pro controller.
