Caution
Your fuse box is old and you are wondering whether it needs replacing with a modern consumer unit. Rewirable fuses, no RCD test button, or a wooden back board are clear upgrade signals.
High risk
Your fuse box or consumer unit is making a humming, buzzing, or vibrating noise.
Emergency
Your consumer unit or fuse box is hot to the touch: this is a fire risk that needs immediate attention. Do not open the cover; turn off the main switch if safe and call an emergency electrician.
Your fuse box is showing signs that it is outdated and no longer providing adequate protection.
If pressing the T or Test button does not switch your RCD off, the RCD has probably failed and the circuits it covers may have no protection against electric shock. Do not keep pressing it. Avoid using outdoor or wet-area appliances on those circuits and book an electrician to test and replace it.
You have a metal fuse box and want to know if it meets current regulations and is safe to use.
Your fuse box or consumer unit is located in the bathroom: a potentially dangerous and non-compliant situation.
Your fuse box uses old rewirable fuses with fuse wire instead of modern circuit breakers.
Low risk
Your consumer unit has no labels, or the labels are wrong: making it impossible to identify which switch controls what.
Describe the job and get a fixed price from a local electrician.
