Series description


Ready for connection, non self-priming water-supply unit with 2 parallel-switched, horizontally arranged high-pressure multistage centrifugal pumps with fixed speed in glanded design of the MHIL series, equipped with BC switchgear.


  • Fully automatic water supply and pressure boosting in residential buildings and small commercial locations.
  • Pumping of drinking water and clean process water and other water mixtures that do not chemically or mechanically attack the materials used and do not contain any abrasive or long-fibre constituents.

Type key

COE Compact pressure boosting system
2Number of pumps
MHILPump series
3Rated volume flow [m3/h]
05Number of pump stages
DM3~ (EM: 1~)

Special features/product advantages

  • System with high-pressure multistage centrifugal pump of the MHIL series made of grey cast iron and stainless steel
  • Hydraulics made of stainless steel in combination with IE2 standard motors for 3~ motors from 0.75 kW and IE1 motor for 1~ motors
  • Two horizontally aligned high-pressure multistage centrifugal pumps of the MHIL series switched in parallel, for flow rates of up to 16 m3/h and delivery heads of up to 55 m
  • BC switchgear: operationally necessary functions are ensured by the electromechanical technology used. The switchgear is accommodated in a plastic cabinet. Starting/stopping the pumps with a pressure switch; low-water cut-out switchgear, motor protection, pump cycling, stop delay of the pumps. An LED display provides information on alarms and pump operation and provides switches for selecting the operating mode

Technical data

  • Mains connection 3~400 V, 50 Hz or 1~230 V, 50 Hz
  • IE2 standard motor for 3~ from 0.75 kW (for 1~ : IE1 standard motor)
  • Fuse A, AC 3 on mains side according to motor power and EVU regulations
  • Max. fluid temperature of +50 °C (+70 °C optional)
  • Operating pressure 10 bar
  • Inlet pressure 6 bar
  • R2'' nominal connection diameter
  • Protection class: IP 54


  • Two pumps of the MHIL 3 to MHIL 5 series per system with an IE2 standard motor for 3~ motors and IE1 for 1~ motors
  • Automatic pump control with BC switchgear specially for the pump management with fixed speed
  • Components that come in contact with the fluid are corrosion resistant.
  • Base frame made of galvanised steel
  • Pipework made of galvanised steel
  • Stop valve on the suction and pressure side of each pump
  • Non-return valve on the pressure side of each pump
  • Pressure switch on the pressure side
  • Pressure gauge on the pressure side
  • Optional low-water cut-out switchgear on the suction side


  • Base frame: made of galvanised steel, to be fastened to a concrete foundation
  • Pipework: Complete pipework made of galvanised steel, suitable for the connection of all standard pipe materials; the pipework is designed according to the hydraulic output of the pressure boosting system.
  • Pumps: Two pumps of the MHIL 3 to MHIL 5 series switched in parallel; all pump components that come in contact with the fluid are made of stainless steel/cataphoretic-coated grey cast iron. KTW/WRAS approval for all components that come in contact with the fluid. More information on the pumps can be found in the "Pressure boosting" chapter.
  • Valves: Each pump is equipped with an ACS-tested ball shut-off valve on the suction and pressure side and with a KTW-tested non-return valve on the pressure side.
  • Diaphragm pressure vessel: A diaphragm pressure vessel is to be designed and installed according to the installation situation.
  • Pressure sensor: A pressure sensor is installed and connected to the BC switchgear on the pressure side of each pump.
  • Pressure indication: On the pressure gauge on the pressure side
  • Switchgear: The system is standard-equipped with a BC switchgear.


For the MHIL 3 and MHIL 5 series:

  • Impellers, diffusers, stage housing made of stainless steel 1.4301
  • Pump housing made of cataphoretic-coated grey cast iron EN- GJL 250
  • Shaft of stainless steel 1.4028
  • O-ring seals made of EPDM
More information on the pumps can be found in the "Pressure boosting" chapter.

Scope of delivery

  • Factory-mounted, ready for connection pressure boosting system checked for functionality and impermeability
  • Packaging
  • Installation and operating instructions

Consulting guide

Pressure reducer

Excessively high or strongly fluctuating inlet pressure requires the installation of a pressure reducer to maintain a constant minimum inlet pressure level. The maximum permissible fluctuation of the inlet pressure is 1.0 bar.

Volume flow

Up to 8 m3/h (111 l/s) system configuration according to DIN 1988 (EN 806); with standby pump up to 16 m3/h (133 l/s), with the standby pumps used for the peak-load operation.

Inlet pressure

The maximum inlet pressure (see Technical data) is to be observed for the system configuration. The maximum inlet pressure is calculated from the maximum unit working pressure minus the maximum pump delivery head at Q = 0.

Low-water cut-out switchgear (WMS)

According to DIN 1988 (EN 806), the installation of a low-water cut-out switchgear is required if the pressure boosting systems are connected directly to a public mains power supply; this prevents the inlet pressure in the mains supply line from dropping to values below 1.0 bar.


The overall system meets the requirements of the following standards and guidelines:

  • EN2006/42/EC
  • EN2004/108/EC
  • CEM 2004/108/EC

The requirements of the standard EN 806 and those of water supply companies must be met with regard to the electrical components.

The requirements of DIN 1988 (EN 806) are to be observed whenever the pressure boosting system is used or operated.

Duty chart

Pump curves


General overview

Edition 2017
Page format A4
Number of pages 72

PDF (46 MB)


Article Number 409
Edition 1602
Version number 04
Page format A4
Number of pages 12

PDF (493 kB)



Article Number 4088957
Edition 0412
Version number 02
Page format A4
Number of pages 15

PDF (1 MB)





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