“Maintenance-free” should not end the ownership conversation. A heat battery may have no sacrificial anode or stored potable water, yet the complete installation still includes controls, pumps, valves, sensors, electrical protection and sometimes other serviceable components.
The short answer
Ask for the maintenance schedule and warranty document for the exact model before ordering. Separate the storage core warranty from cover for electronics, controls and labour. Confirm who will diagnose a fault locally and how long essential parts are expected to remain available.
What can need attention
The answer depends on system design. A periodic visit may include checking for leaks, fault codes, control settings, safety devices, strainers, pump operation and visible damage. An installer should explain which checks are owner tasks and which require a competent person.
If the unit works with a heat pump, boiler or solar diverter, those components keep their own service requirements. One “system” may therefore have several maintenance schedules.
Read the warranty as a process
Check:
- the length of cover for the core, controls and other parts
- whether labour, call-out and carriage are included
- required servicing and record keeping
- registration deadlines and installer requirements
- exclusions for water quality, electrical supply or incorrect settings
- whether cover transfers when the home is sold
- the remedy if the original installer stops trading
A long headline warranty can be less useful than a shorter cover period with clear labour terms and a functioning service network.
Plan for faults and end of life
Ask whether the home keeps an immersion, boiler or other backup when stored heat is exhausted or the unit is offline. Find out which components are replaceable without removing the storage core.
At end of life, ask who accepts the unit, whether the storage material and enclosure can be recovered, and what removal may involve. Treat unverified recycling percentages cautiously.
Keep a small system file
Save the quote, design assumptions, serial number, commissioning sheet, warranty registration, manuals and service record together. Photograph pipe and cable routes before they are boxed in. Record the normal control settings so an accidental change is easier to spot.
Your next step
Before paying a deposit, request the warranty and maintenance schedule as documents rather than accepting a verbal summary. Add the likely service cost and any excluded labour to your whole-cost comparison.
Sources
Primary and independent references checked by our editorial team.
- Energy storage options explained — Energy Saving Trust Checked 10 Nov 2026