Unvented Hot Water System

D M Jones Electrical Contractors specialise in Design & Install, Breakdowns, Leaks, Component Upgrades, Servicing, Tank Removal.

What is an Unvented Hot Water Cylinder?

An Unvented Hot Water Cylinder is a pressurised system which is fed directly from the cold mains water feed and therefore can deliver hot water at mains pressure, which is great for improving the performance of your shower and bath.

Unvented Cylinders don’t require a cold water storage tank, which is ideal if you are pushed for space as well as offering more flexibility when sitting the cylinder.

The water can either be heated directly via an immersion heater or indirectly via the central heating system.

Unvented hot water cylinders require expansion vessels to be fitted to allow the expansion of water in the system as it heats up. Unvented cylinders also come with other safety mechanisms, such as pressure relief valves and twin thermostats.

To ensure safety and to comply with building regulations, it is essential that an unvented hot water cylinder is installed and serviced annually by an approved licensed engineer.


  • Creating space in the loft by removing the header tank and minimises the risk of water damage above ceilings
  • Hot water at mains pressure
  • Hot water keeps its temperature for longer
  • Less chance of contamination
  • Can be installed anywhere in the property

Our Hot Water System Electrical Technicians are:

  • Polite, reliable and trustworthy
  • Fully trained, skilled and experienced
  • CRB checked
  • Fully licenced and insured
  • Equipped with all the latest testing instruments
  • Fully conversant with all the latest regulations and technology
  • Uniformed for safety and security
  • Conversant in both Welsh and English
  • Fully licensed, bonded and insured
D M Jones Electrical Contractors has been providing efficient, reliable and superior electrical services to residential, commercial, industrial and agricultural clients in Aberystwyth and surrounding mid and west Wales areas.
Call 01970 617744 to see how we can help.