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Designed for sealed systems and is compact in size, easily fitting into a standard domestic airing cupboard.


Combination of an electric flow boiler with a hot water storage cylinder and a pre-plumbed, factory fitted circulating pump. Electromax can provide wet central heating and a hot water supply, both at the same time if required, with only a mains electrical connection and cold water supply needed.

The integral duplex stainless steel unvented cylinder has a 180 L capacity, delivering mains pressure showering, fast filling baths and a balanced supply to multiple tap outlets. Available in two domestic kW sizes.

Features and benefits:

  • Floor-mounted design.
  • Controllable, efficient wet central heating.
  • Programmable room thermostat to accommodate a wide range of off-peak tariffs.
  • Uses standard radiators and thermostatic radiator valves.
  • Designed for sealed systems.
  • Models are available for underfloor heating systems.
  • High-performance domestic hot water from unvented direct hot water cylinder.
  • Cylinder manufactured from high quality duplex stainless steel.
  • No flue and no fuel tanks allow flexible installation location.
  • Silent operation.
  • Automatic pump exercise feature - for periods when the boiler is switched off.
  • Front control panel indication to show boiler status.
  • Proven solid-state technology for long life.
  • Soft start and zero volt switching to avoid power surges.
  • Minimum/ maximum control adjusts the water temperature output from the boiler.
  • Minimal service and maintenance costs.
  • No requirement for annual gas safety certificate - consult manufacturer for details.
  • Ten-year on-site parts and labour warranty on the cylinder, two years on the boiler and other controls
  • Designed, engineered and manufactured in the UK.
  • Fully Energy related Products (ErP) compliant, CE marked and Kiwa approved.


Designed for sealed systems and is compact in size, easily fitting into a standard domestic airing cupboard.

General information
Specification data - Electric boilers
Product Reference

Electromax 6 kW - Radiator

6 kW output.

Electromax 6 kW - Underfloor

6 kW output.

Electromax 9 kW - Radiator

9 kW output.

Electromax 9 kW - Underfloor

9 kW output.

Standard product features

Size (h x w x d):

1476 x 550 x 600 mm.

Weight (empty/ full):

74/ 256 kg.


180 L.

Energy related Products (ErP) rating:


Technical characteristics:

  • Off peak/ boost immersion heater input: (kW) 3 kW (at 240 V); 2.8 kW (at 230 V).
  • Rated pressure: 6 bar.
  • Pressure Reducing valve: 3.5 bar.
  • DHW expansion vessel:18/3.5 L/bar.
  • Temperature /pressure relief valve: 90/10ºC/bar.
  • Combined thermostat: 10–70ºC.
  • Resettable thermal cut-out: 85ºC.
  • Minimum insulation thickness: 40 mm.
  • Heat up time off peak: Δt (temperature difference) at 45ºC: 180 minutes; Δt (temperature difference) at 50ºC: 200 minutes.
  • First hour performance 3 kW boost element Δt 45ºC: 57 L.
  • Heat loss: 1.95 kWh/24 hours.
  • Electrical supply voltage: 220–240 V.
  • Electrical supply frequency: 50 Hz.
  • Internal fuse rating – pump supply: 2 A.
  • Primary system operating pressure (minimum): 1 bar.
  • Primary system pressure relief valve setting: 3 bar.
  • Primary system expansion vessel: 12/1 L/bar.
  • Primary flow temperature: Radiator models: 65–80ºC; Underfloor models: 30–60ºC.
  • Water heating energy efficiency class: C.
  • Seasonal space heating energy efficiency class: D.
  • Seasonal space heating energy efficiency: 37%.
  • Annual energy consumption: 6 kW models: 12 986 kW/h; 9 kW models 19 472 kW/h.

Third party certifications
  • Kiwa : Approved
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