Consider water boosting when fitting a new boiler

Installing a new boiler in a property can sometimes have a detrimental effect on water pressure. Stuart Turner explains how installers can overcome the problem.

With homeowners choosing to extend or renovate their properties, maintaining sufficient water pressure can become a challenge for installers. Particularly if changing from a gravity fed (vented) system to an unvented system where a combi boiler or pressurised hot water cylinder is installed to free up valuable space and the homeowner wants additional bathrooms.

Unvented systems rely on the mains water supply to directly feed the combi boiler or pressurised hot water cylinder. Whilst these systems tend to be smaller and more energy efficient, they are reliant on the incoming mains water pressure to work efficiently. Unfortunately, they can sometimes suffer from poor incoming mains water pressure, resulting in a first-floor bathroom being unable to provide an invigorating shower.

While this is not the fault of the boiler itself, multiple bathrooms and water using appliances mean multiple outlets drawing water at the same time. A shower can turn to a trickle when a tap is opened elsewhere, leaving a potential issue for the installer to overcome.

OFWAT (Water Services Regulation Authority) states that an average water pressure of 0.7 bar should be maintained at the communication pipe but as this is measured at pavement level and not at the outlet, actual water pressures can vary throughout the property. For instance, water pressure could decrease to as little as 0.2 bar on higher floors. With luxury showers and taps typically requiring pressures of 1 bar or more, homeowners could find they have insufficient water pressure.

What can you do?

One solution is to recommend a mains water boosting system in conjunction with the new mains fed boiler. Fitted directly onto the incoming mains water supply, mains water boosting systems work to increase water pressure throughout the property, but remember, UK water regulations specify that systems connected directly to the mains supply must be regulated to draw a maximum of 12 litres per minute, so you must choose a water regulations compliant and WRAS approved solution.

The Mainsboost™ range by Stuart Turner is proving to be a popular approach. They are WRAS approved, water regulations compliant and simply connect directly to the incoming rising main to solve the problem of low or intermittent mains water pressure and flow.

Things to consider.

Installers will need to check a few things to determine which Mainsboost product is right for the property. To ensure the system is sized correctly, check the following:

  • How many outlets the system may need to supply at any one time, along with the number of occupants in the home.
  • The existing incoming mains pressure and flow rates along with the size of the mains supply and pipework.
  • The type of system required will also be determined by pressure requirements, as a guide 1.5 - 2.0 bar systems for taps, and 2.0 to 4.0 bar systems to provide higher flow rates for larger outlets, such as showers.

Before replacing an existing vented system with a combi boiler or pressurised hot water cylinder, take time to explain the effect this may have on the water pressure and where necessary, recommend the installation of a proactive solution such as the Stuart Turner Mainsboost™ range, to prevent water pressure problems occurring. Not only will this result in a better informed and satisfied customer, it also offers installers a valuable opportunity to upsell and generate an additional revenue stream.

A Stuart Turner Mainsboost™ system allows homeowners to run multiple outlets simultaneously, without a reduction in water pressure and flow and are available in a variety of sizes for a wide range of properties. Simple really. To find out more visit:


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