Common signs of a faulty RCD include: tripping on circuits with no detectable earth fault (nuisance tripping), failing to trip when tested using the test button, taking longer than 300ms to trip at rated current (sluggish operation), or failing to reset after a genuine fault has been cleared. We test RCDs to BS 7671 requirements using calibrated equipment to confirm performance.

Signs of a faulty MCB include: tripping immediately when reset with no apparent fault on the circuit, failing to trip when the circuit is genuinely overloaded, not resetting at all after a fault has been cleared, or physical damage to the device. Note that a correctly functioning MCB tripping repeatedly indicates a genuine circuit fault, not necessarily a faulty breaker.

Consumer unit component replacement is not recommended as a DIY task, even for those with some electrical knowledge. The incoming mains supply to the consumer unit remains live even when the main switch is off, creating a genuine risk of fatal electric shock. In addition, using an incorrect specification replacement creates a safety risk that may not be apparent but can cause fire or personal injury. We always recommend using a qualified electrician.

A single MCB or RCBO replacement typically costs £80–£150 including the part and labour. An RCD replacement costs £100–£200 depending on the brand and type. We carry common components on the van for same-day replacement. Call us with your consumer unit brand and the circuit/device affected for an immediate fixed-price quote. Pricing is consistent across all East London postcodes.

Yes — if you have a consumer unit with MCBs and a split-load RCD arrangement, we can upgrade individual circuits to RCBO protection on a circuit-by-circuit basis. This provides superior protection — each circuit is individually protected against both overload and earth faults. We advise on the most cost-effective upgrade approach for your specific board during the site visit.

Replacing a like-for-like MCB, RCD, or RCBO in an existing consumer unit is generally not notifiable under Part P. However, if the replacement involves any circuit alteration, or if the board is replaced in its entirety, it becomes notifiable. We assess the scope and self-certify all notifiable work with Building Control at no extra cost.

Yes — we carry common MCBs, RCDs, and RCBOs from Hager, Wylex, MK, and Schneider on the van, allowing same-day replacement for most consumer unit faults. Call 07852 280 518 and tell us your board brand and the affected circuit — we will confirm availability and our earliest attendance time across Tower Hamlets, Newham, Hackney, Waltham Forest, and all East London areas.

Many older consumer units across East London — particularly in Victorian and Edwardian properties in Tower Hamlets and Hackney — have outdated dual-RCD arrangements, old MCB designs, or even older rewirable fuse boards. Where a single component can be replaced cost-effectively, we will do so. Where the board is fundamentally outdated or has multiple failing components, we will provide an honest recommendation for a full consumer unit upgrade, explaining the safety benefits and cost differences.

Yes — upgrading from a dual-RCD arrangement to individual RCBO protection on every circuit is strongly recommended for Victorian and Edwardian properties across East London. These properties often have more circuits than modern homes (due to decades of additions), and a dual-RCD arrangement means a single fault can knock out half the property's circuits simultaneously. Individual RCBO protection means only the affected circuit trips — the rest of the property remains powered. We carry out RCBO upgrades across all East London boroughs.

Yes — RCD replacement in HMOs is a common and important service across East London. HMOs have higher electrical loads than single-occupancy properties, and RCDs in HMO consumer units are subjected to more frequent operation and greater stress. A faulty or nuisance-tripping RCD in an HMO can affect multiple tenants simultaneously. We carry out RCD testing and replacement in HMOs across Tower Hamlets, Newham, Hackney, Waltham Forest, and all East London boroughs, with full certification issued on completion.

Yes — we cover Hackney (E8 Dalston, E1/EC2 Shoreditch) and Waltham Forest (E17 Walthamstow, E10 Leyton) for same-day RCD and MCB replacement. These areas have a high proportion of older properties with consumer units that are more prone to protection device failures. Call 07852 280 518 for the fastest response in your area.