Four fire engines and around 25 firefighters were called to a fire at a residential care home on Gunnersbury Lane in Acton.
A small part of a water storage heater in a boiler room on the second floor of the building was damaged by fire. Around 30 people were evacuated by staff before the Brigade arrived. There were no reports of any injuries.
A London Fire Brigade spokesperson said: “On arrival crews noticed a strong smell of burning and carried out a search of the building.
“Firefighters used thermal imaging cameras to locate the fire and worked incredibly hard to quickly bring it under control.”
The Brigade was called at 0220 and the fire was under control by 0326. Fire crews from Acton, Chiswick, Ealing and Park Royal fire stations attended the scene.
The fire is believed to have been caused by an electrical fault in a water heater tank.