Most homeowners understand the importance of servicing their boiler each year, but the unvented hot water storage system (aka unvented hot water cylinder) often gets overlooked. If you have one in your home, it plays just as big a role in your comfort and safety — and it also requires an annual inspection by a qualified and registered engineer.
As OFTEC and Gas Safe registered engineers, also qualified & registered to install and service unvented hot water storage systems, please let us explain why annual servicing isn’t just recommended, but essential.
1. Safety Is Critical
Unvented hot water systems store water at high pressure and high temperature. To keep them safe, they are fitted with multiple safety devices such as pressure relief valves, temperature relief valves, and expansion vessels.
- If these fail, the system could become dangerous.
- During a service, we test and verify that all safety components are working as designed, giving you complete peace of mind.
2. Maintaining Efficiency
Over time, scale and debris can build up inside the cylinder and its controls. Regular servicing ensures:
- The system heats water efficiently.
- Controls and thermostats are accurate.
- Energy use stays as low as possible.
This means you’re not wasting money heating water inefficiently.
3. Extending System Life
Like your boiler, an unvented hot water cylinder represents a significant investment. Annual servicing protects that investment by reducing wear and spotting small issues before they become expensive faults. With proper care, these systems can last many years longer.
4. Protecting Your Warranty and Insurance
Manufacturers require annual servicing by a qualified engineer to keep the warranty valid. Similarly, many insurers expect proof of annual checks if you ever need to make a claim. Skipping a service could leave you unprotected.
5. Legal Requirement for Competence
Not just anyone can work on unvented hot water systems. By law, only engineers holding the correct G3 qualification (often referred to as “unvented ticket”) can service or install them. We are trained and registered to do this safely and legally — so you know the job is being carried out by someone competent and certified.
Final Word
Your unvented hot water storage system is every bit as important as your boiler. Regular annual servicing ensures it remains safe, efficient, reliable, and compliant. By choosing qualified and registered engineers, you’re protecting your home, your family, and your investment.
If your cylinder hasn’t been inspected in the last 12 months, now is the time to book.