What affects the unvented cylinder installation cost

• Type and size of the cylinder, for example 120 litre direct or larger indirect models
• Whether this is a direct replacement or a first time install
• Cold water main size, pressure and flow requirements
• Discharge pipe route and termination to outside
• Relocating the cylinder to a new position
• Brand selection, controls, and any extras such as scale protection

Direct replacement costs

If you already have an unvented hot water cylinder and are replacing like for like, you will usually be at the lower end of the scale. A straightforward swap of a 120 litre direct unvented cylinder can start from about £550 for supply and fit when no upgrades are needed. Larger sizes, premium brands and new ancillary parts will add to the total.

Cold water main upgrades

First time installations often require attention to the incoming cold water main. A dynamic pressure and flow test should be carried out to confirm suitability. If the main from the stop tap to the cylinder is undersized, upgrading the pipework is recommended to ensure performance at multiple outlets. This extra labour and material will increase the unvented cylinder installation cost.

Discharge pipe routing

Every unvented cylinder needs a correctly sized and routed discharge pipe to a safe visible termination outside. Longer routes, difficult access, core drilling and boxing in can add time and materials. The more complex the route, the higher the install cost is likely to be.

Relocating the cylinder

Moving the cylinder to a new location involves re working hot, cold and primary pipework, power supplies and controls. Expect additional cost compared with a simple like for like replacement in the existing position.

Good locations for an unvented cylinder

An internal garage can be a cost effective spot when the stop cock is nearby. Upgrading the water main is usually simpler and the discharge pipe route to outside is often shorter, which helps control the overall unvented cylinder installation cost. Airing cupboards and utility rooms also work well when space and access allow.

Local service for Bourne and PE10

We install and replace unvented hot water cylinders across Bourne PE10 and nearby towns including Spalding, Stamford, Market Deeping and Peterborough. All work is carried out by G3 qualified engineers with Building Control notification where required.

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Unvented cylinder installation FAQs

What is the average unvented cylinder installation cost

Most homes fall between £550 and £2,000 depending on cylinder size, brand, discharge routing, water main upgrades and whether the cylinder is being relocated.

Do I need to upgrade my cold water main

Often yes for first time installs. A pressure and flow test will confirm if an upgrade is needed to deliver good performance at multiple taps and showers.

How long does installation take

A direct replacement is typically completed in one day. First time installs or relocations can take longer due to pipework changes and discharge routing.

Will the installation be notified to Building Control

Yes, new unvented cylinder installations are notified. Keep the documentation and your service records for warranty and insurance purposes.