System Boiler

System boilers are the modern version of the Boiler & Cylinder combo. The cylinder and airing cupboard are kept as is the Cold Water storage tank in the loft. The f&e Tank in the loft (the small one used for heating) is removed.

The system boiler incorporates the Sealed system (pressurised pipework) characteristics of the combination boiler, ie it is filled off the mains and air locks are non existent. These boilers can be installed with internal (boiler) or external (airing cupboard) controls. They are ideal for houses where a cylinder is needed because of increased hot water demand (3people+)


  • Sealed/pressurised heating system

  • No air locks

  • No loft tank

  • No noisy pumps (internal controls)

  • Still have an immersion if boiler fails

  • Still have a cylinder of hot water if the mains fails


  • Still have a tank in the loft for hot water

  • Not mains pressure hot water

  • Hot water not instant - cylinder fed

The system boiler is well suited to properties where the plumbing is in good condition. if pipework is dubious then we recommend that it is replaced before installing a pressurised heating system. Recently (last 10yrs) the best system boilers started to include all the controls internally and this has helped reduced running costs via low voltage circuits within the boiler. this has cut emissions and usage costs. we only recommend the best quality boilers on the market.

Brands we like

Viessmann Combination boiler  

The comprehensive product range from Viessmann includes advanced heating systems for all fuel types and for every output range from 1.5 to 20 000 kW. The range is divided into the categories 100, 200 and 300, both technically and in terms of price and so is able to offer a suitable solution for any requirement, with everything supplied from a single source, with perfectly matching system components.

Vaillant Combination boiler  

Whether you use natural gas, LPG, electricity or renewable energies, Vaillant offers efficient solutions for all energy sources. The result: domestic comfort that is perfect for you.

boiler service

gas boiler service

Power flushing

Power Flushing is when heating systems are forcibly cleansed with aggressive chemicals using water at high velocity.

Radiators cold at the bottom or centre?

Radiators not heating at all?

Is your boiler banging or noisy?

Boiler cutting out due to sludge in pumps?

It takes a long time for radiators to heat up?

If the answer is YES then your system probably needs a power flush call us to find out more.