Electric Storage Heaters in London Flats: What an EICR Looks For

Thousands of London flats, especially in post war blocks and council built estates, are heated by electric storage heaters rather than gas. They run on a separate off peak supply, and that extra circuit work is something we look at closely during an EICR. This guide explains how storage heater systems are wired, what we check, and the problems we find most often.

How storage heaters are wired

Storage heaters charge up overnight on cheaper electricity and release the heat during the day. To do that, the flat usually has two parts to its installation: the normal supply for lights and sockets, and an off peak supply controlled by the meter or a time switch. Each heater has its own circuit, normally ending at a switched fused outlet or flex outlet next to the heater. Many flats also have an immersion heater for hot water on the same off peak arrangement.

What an EICR checks

• Each storage heater circuit is protected by a device that matches the cable and the heater rating.
• The heater outlets, flex and connections show no signs of overheating.
• The off peak consumer unit or switch fuses are in good condition, labelled, and have suitable protection.
• RCD protection where it is needed, and earthing and bonding for the whole flat.
• Insulation resistance on every circuit, which can drop on old heater wiring.

Common problems in London flats

• Old rewireable fuse boxes or separate switch fuses for the off peak circuits, often decades old.
• Scorched heater outlets and brittle flex from years of heavy load.
• Heater circuits with no labels, so nobody knows which fuse feeds which room.
• Heaters replaced with bigger models without checking the circuit.
• Two separate boards in the cupboard, one of which has no RCD protection at all.

Problems like these are often coded C2, which makes the report unsatisfactory. Our guide to what happens after an unsatisfactory EICR explains the deadlines landlords need to meet.

Upgrading the heating

Some landlords take the chance to swap old heaters for modern high heat retention models, panel heaters or a heat pump. Whatever you choose, the circuits and consumer unit need to suit the new equipment. Our guide on getting the consumer unit checked before a heat pump or solar covers what to look at first.

Book an inspection

Energy North Ltd carries out EICR inspections on all-electric flats across North, East and West London. Our City & Guilds certified electricians can usually attend within 48 hours, and certificates are emailed the same day. For residents with parking, see our EV charger installation page too.