Hot Water Break Tank & Pump MIDI-HS 230 V

£2,565.00 £3,078.00 inc. vat

In stock


Wall mounted break tank and pump assembly delivers a constant supply of hot water with Fluid Category 5 backflow protection by virtue of the integral Type AB air gap. The set utilises the existing hot water supply, preventing the need for a secondary water heater.

Hot water has long since caused problems when it comes to Fluid Category 5 protection, due to the requirement of an air gap and thus a storage cistern. The hot water cannot be maintained in the cistern, as it would be at the optimum temperature for encouraging the growth of Legionella bacteria. The BTMIDI-HS unit overcomes this issue by purging the contents of the cistern via a bypass solenoid valve once the demand has been met, therefore no water is stored while the unit is not in use.

Eliminating the necessity for an additional water heater is advantageous as it results in lower power and space requirements. The set is housed in a compact stainless steel cabinet ready for wall mounting.

The unit automatically switches on when a pressure drop is detected and use a PLC (Programmable Logic Controller) to manage the filling solenoid, pump and bypass solenoid. A BMS fault alarm is fitted as standard, which activates the fault lamp if the tank water level is too low. The pump has a “soft start” feature, which avoids water and electrical surges. The unit is quiet since the pump is mounted on anti vibration mounts with flexible stainless braided internal hoses.

An upstream thermostatic mixing valve is recommended to regulate the temperature – e.g. Arrow Valves model TMV5213.


Birthing pools; Dog grooming showers; Assisted baths; High flow rate showers; Butchery & meat equipment; Applications deemed to be Category 5 by water company

Product Specification
  • Backflow Prevention Yes
  • Cistern Size 3.5 Litres
  • Inlet Size 15 mm
  • Max. Flow Rate 0.20 Lt/s
  • Outlet Size 15 mm
  • Powered Yes
Specification Clause

Where indicated on the drawing a Hot Water Break Tank & Booster Set – model BTMIDI-HS shall be installed – as manufactured and distributed by Arrow Valves Ltd – Tel 01442 823123 The output pressure shall be 0.17 lt/s @ 2 bar and a closed valve head of 3.1 bar. The unit shall be housed in a stainless steel cabinet which shall be mounted on a wall at a serviceable height. The internal cistern shall provide a type AB air gap. The cistern level shall be controlled automatically by a servo solenoid valve operated via stainless steel conductive electrodes and controller. A volt free BMS fault relay shall be provided – model BTBMS3. A low-level pump cut-out shall automatically reset once the cistern is sufficiently full. The pump shall be continuously rated, feature brass wetted parts and be acoustically attenuated with anti-vibration mounts. The 22 mm overflow shall discharge in a safe and conspicuous manner. A 15 mm supply is required, which must maintain a dynamic pressure of 1.0 bar. The manufacturer’s flexible hose with servicing valve and strainer (supplied) shall be installed.

Data Sheets


bthsdatasheet.pdf (384.49 KB)


Installation Guide

bthso_mmanual_1.pdf (711.97 KB)


Additional Information