The general expert consensus is to turn on the heat when indoor temperatures consistently drop to around 18°C (64°F) or lower, or when outdoor temperatures fall below about 15°C (59°F). Many recommend waiting until nighttime outdoor temperatures dip below 55°F (around 13°C) or indoor temps feel uncomfortably cold. In the UK and similar climates, mid-October (around October 17-20) is often cited as the right time, aligning with temperatures dropping below 15°C outside. For health and comfort, maintaining indoor temperatures near 18°C is advised, especially for vulnerable groups like children and the elderly. Heating should be used when occupants start feeling cold, and it can be economical to time heating to when people are home and active rather than running it all day. In summary:
- Turn on heat when indoor temps drop below about 18°C (64°F) or outdoor temps drop below 15°C (59°F).
- Mid-October is a common recommended time for starting heating season in temperate climates.
- Use programmable thermostats to optimize heating timing for comfort and efficiency.
- Adjust based on personal comfort, health needs, and home insulation.
This guidance balances energy efficiency with comfort and health considerations.