What is this?
When power loss follows a predictable daily pattern, it usually relates to a regular event — an appliance on a timer, a heating system switching on, or even a neighbour's high-draw equipment affecting the supply. Time-related patterns are actually helpful for diagnosis.
Common causes
- Appliance on a timer drawing heavy current when it switches on (e.g., immersion heater, storage heater, water heater)
- Economy 7 or off-peak switching causing a surge
- Heating system starting up and overloading a circuit
- Faulty time-controlled equipment like a boiler or heated towel rail
- Supply voltage dip at peak times if the local network is overloaded
Is it dangerous?
A predictable pattern suggests the cause is identifiable and fixable. It is not an emergency, but it should be investigated because repeated tripping stresses the electrical system. The underlying issue may worsen over time.
Can I fix it myself?
Note the exact time the power goes off and what appliances or timers are set for that time. Check if an immersion heater, storage heater, or other timed appliance switches on at that point. Try disabling timed appliances one by one to identify the culprit.
When to call an electrician
Call an electrician if you cannot identify the timed appliance causing the issue, if disabling timers does not fix it, or if the problem persists. An electrician can test the circuit capacity and identify if the circuit is overloaded.
What will an electrician do?
Review the timing pattern and identify appliances running at that time
Test the circuit capacity and loading
Check timed appliances for faults (especially immersion heaters and heating elements)
Redistribute loads across circuits if overloaded
Install a dedicated circuit for high-draw appliances if needed
Typical cost
£80 – £250
Diagnosis is usually straightforward once the timing pattern is established. Costs increase if a new dedicated circuit is needed.
