Hot water is a fundamental aspect of modern living, and unvented hot water systems have become a popular choice for homes across the UK due to their ability to deliver high pressure, consistent supply, and energy efficiency. However, like any plumbing and heating system, unvented cylinders and associated components eventually require replacement—either due to age, wear, performance issues, or updated efficiency standards.
For property owners in Wiltshire, the replacement of unvented hot water systems must be approached with professionalism, safety, and compliance in mind. At Cheeseman Plumbing & Heating, we provide fully qualified replacement services for unvented systems across the region, ensuring your home remains safe, efficient, and fully compliant with UK building regulations.
What Is an Unvented Hot Water System?
An unvented hot water system is a type of pressurised system that stores hot water in a sealed cylinder. Unlike traditional vented systems, it does not require a cold water storage tank in the loft. Instead, the cylinder is fed directly by the mains water supply, providing high pressure and rapid flow rates throughout the home.
These systems are particularly well-suited to properties with multiple bathrooms or high hot water demand. They offer excellent water pressure, faster filling of baths and showers, and reduce the need for additional storage space.
Why Replacement May Be Necessary
Although unvented systems are robust and long-lasting, several factors can necessitate their replacement:
- Age and wear: Most unvented cylinders have a service life of 10–20 years, after which internal components may deteriorate.
- Limescale build-up: Especially in hard water areas like Wiltshire, scale accumulation can reduce efficiency and lead to failure.
- Corrosion or leaks: Over time, the internal lining or fittings may corrode, affecting system integrity.
- Safety compliance: Modern safety standards and building regulations may require upgrades to outdated or improperly installed systems.
- Energy efficiency: Newer cylinders offer superior insulation and energy ratings compared to older models.
Legal and Safety Requirements
It is essential to note that unvented hot water systems must be installed, maintained, or replaced only by engineers with the appropriate qualifications. Under Building Regulations (Part G3), only installers with Unvented Hot Water G3 Certification are legally permitted to carry out work on these systems.
At Cheeseman Plumbing & Heating, all of our engineers are fully qualified and certified to handle the replacement of unvented systems. Our work is registered with local authorities where required, and all installations are carried out in accordance with current legislation and manufacturer specifications.
Our Replacement Process
We follow a structured and safety-focused process to replace unvented hot water systems across Wiltshire:
1. System Assessment
Our engineers will inspect your existing system and assess your current hot water demand, property layout, and water pressure to determine the most suitable replacement.
2. Product Recommendation
We recommend high-quality, energy-efficient cylinders from trusted brands such as Heatrae Sadia, Gledhill, Megaflo, and Telford, ensuring reliable long-term performance.
3. Safe Decommissioning
The existing cylinder is carefully drained, disconnected, and removed in compliance with safety procedures.
4. New Installation
We install the new cylinder, pressure controls, safety valves, and expansion vessels as needed. All pipework is reconnected and tested for leaks and flow efficiency.
5. Certification and Handover
Upon completion, we provide the relevant certification, warranty documentation, and a user handover so you understand how your system operates.
Benefits of Upgrading to a Modern Unvented System
1. Improved Energy Efficiency
New cylinders have superior insulation, reducing heat loss and energy consumption. Many models now carry ErP A-ratings, supporting the UK’s push toward energy conservation.
2. Enhanced Safety Features
Modern systems include multiple safety components such as temperature and pressure relief valves, expansion control kits, and thermostatic controls.
3. Higher Hot Water Capacity
Updated cylinders are often more compact yet more efficient, allowing for better hot water availability in busy households.
4. Smart Controls
Many newer models are compatible with smart thermostats and home automation, allowing greater control over energy usage.
5. Manufacturer Warranties
Leading brands offer warranties of up to 25 years on unvented cylinders, giving homeowners peace of mind and long-term protection.
Cost Considerations
The cost of replacing an unvented hot water system in Wiltshire depends on several factors, including:
- Cylinder size and brand
- Installation complexity
- Additional work (e.g. replacement of expansion vessel or pressure relief components)
- System upgrades or adjustments
On average, a full replacement typically ranges from £1,000 to £2,500, including supply, labour, and certification. At Cheeseman Plumbing & Heating, we offer clear, fixed quotations with no hidden charges following an on-site assessment.
Why Choose Cheeseman Plumbing & Heating?
For over 40 years, we have built a reputation for reliable, safe, and honest plumbing and heating services across Wiltshire. When it comes to unvented hot water systems, our clients trust us for:
- G3-certified engineers with full legal compliance
- Premium products from leading manufacturers
- Transparent pricing and detailed quotes
- Full certification and building control notifications
- Responsive customer service and aftercare support
We serve homes in Melksham, Trowbridge, Devizes, Westbury, Chippenham, Corsham, and surrounding areas.
Conclusion
The replacement of unvented hot water systems in Wiltshire should always be handled by certified professionals with a strong understanding of safety regulations, system design, and energy efficiency. Whether your current system is outdated, underperforming, or in need of urgent replacement, Cheeseman Plumbing & Heating is here to provide a seamless, compliant, and long-lasting solution.
Contact our team today to schedule an assessment or request a quote. We are committed to delivering safe, efficient hot water solutions for every home we serve.