Four fire engines and around 25 firefighters tackled a fire at a shop with dwellings above on Fore Street in Edmonton.
Most of a five roomed flat on the first floor was damaged by the fire. There were no reports of any injuries.
The fire is believed to have been accidental and was caused by overloaded electrics for a fridge freezer.
A London Fire Brigade spokesperson said: “If your white goods start making a strange noise, don’t ignore it. If you think there’s a problem always unplug it and contact the manufacturer or a qualified repair technician.
“Most fires where white goods are the source of ignition are not down to anything you have done – so always make sure you register your appliances as you’ll be informed if any issues are identified with the product you’ve bought.”
One of the Brigade's 32-metre turntable ladders was used at the scene to help fight the fire from above.
Control Officers took the first of four calls at 1530 and mobilised crews from Edmonton, Tottenham and Enfield fire stations to the scene. The incident was over for firefighters at 1636.