Unvented Hot Water · G3
Qualify to work safely on unvented hot water systems.
A focused one-day course for experienced plumbing and heating engineers covering the installation, commissioning, servicing and maintenance of hot water systems, including unvented systems.
- One-day course
- VAT included
- Certification included
Who the course is for
For engineers working with modern hot-water systems.
This qualification is intended for plumbing and heating engineers involved in hot water systems, solar thermal systems or air and ground source heat pumps.
Candidates must be experienced in the installation of cold and hot water systems. They must also hold either recognised competence in gas, oil or solid fuel, or—for those working in plumbing—an NVQ Level 2 or equivalent plumbing qualification or suitable plumbing experience.
Basic knowledge of the Water Supply (Water Fittings) Regulations is desirable, and candidates should be familiar with Approved Document G before attending. We may request evidence of qualifications or experience before confirming eligibility.
Qualification details
Course facts.
- Certificate
- LCL Awards Hot Water Systems and Safety certificate, including Unvented Hot Water
- Qualification code
- HWSS
- Certificate validity
- Five years
- Scope
- Systems up to 500 litres capacity and 45kW power input
- Assessment
- Multiple-choice questions, short written responses, scenario questions and observed practical tasks
- Renewal
- A reassessment route is available for candidates renewing an existing qualification
Course content
What you’ll cover.
Practical knowledge aligned with current legislation and safe working practices.
- Approved Document G and relevant regulations, standards and guidance
- Hot-water expansion and storage principles
- System design and installation considerations
- Components, safety controls and discharge arrangements
- Commissioning, maintenance and servicing
- Health and safety considerations
Included when you book
Exclusive TomKat pre-course preparation guide included.
Every learner who books our Unvented Hot Water G3 course receives our illustrated preparation guide before attending. It covers system principles, key components, safety controls, discharge requirements, commissioning and original self-check questions to help you arrive ready for the course.
The guide supports preparation but does not replace training, assessment, current legislation, standards or manufacturer instructions.Course prices
Choose training or assessment only.
Both prices include VAT and certification.
Competent Person Schemes
Certificate and registration are separate.
Successful completion supports an eligible engineer’s application to an appropriate Competent Person Scheme. The certificate alone does not grant self-certification; scheme registration is separate. Where the installer is not registered with an appropriate scheme, notifiable work must follow the Building Control route.
After qualifying
How do I notify an unvented cylinder after qualifying?
Your G3 certificate demonstrates your competence to work on unvented hot-water systems. It does not automatically make you a member of a Competent Person Scheme or give you access to a notification portal.
For installations in England and Wales, the correct route depends on the work completed and the schemes your business belongs to.
Gas work is included in the same job
If you are Gas Safe registered, hold the relevant gas categories and have a current G3 qualification recorded with Gas Safe, you may be able to notify the gas work and cylinder through Gas Safe Register.
It is a cylinder-only job with no gas work
If Gas Safe will not accept the notification because no eligible gas work formed part of the job, you must either:
- notify through another Competent Person Scheme covering hot-water systems and unvented cylinders; or
- arrange Building Control approval before starting the installation.
Another engineer cannot simply notify or sign off work they did not carry out.
If you are not registered with a suitable scheme
Contact Building Control before starting the work.
Contact your local authority Building Control department or a registered building control approver before starting the installation. Charges vary by area and the work involved, but a single application will often cost a few hundred pounds.
Government guidance: how to apply for Building Regulations approval ↗Remember: G3 demonstrates competence. Competent Person Scheme membership provides a self-certification route. Building Control is the alternative where you cannot self-certify.
This guidance relates to England and Wales. Different notification and building-control arrangements apply in Scotland and Northern Ireland.
Planning your heat-pump qualifications?
We’ll help you understand the full pathway.
Tell us what qualifications you already hold and what work you want to undertake.