A number of Hotpoint, Indesit & Creda tumble dryer owners have been warned their appliances may pose a fire risk.
Two types of tumble dryers, condenser & vented dryers, manufactured by Indesit, were sold under the three brands in the UK & other countries over the last 11 years.
The firm is in the process of contacting affected consumers, who were warned not to leave their appliances unattended & to clean fluff from the filter after each use.
In "rare" cases a build-up of lint can come into contact with the dryer's heating element, which could pose a fire risk, the manufacturer explained.
Customers can check online if their appliance is among those affected by keying in the model & serial number on the Indesit website.
A safety warning on the Indesit & Hotpoint websites said: "In some rare cases, excess fluff can come into contact with the heating element & present a risk of fire."
An Indesit spokesman told ITV: "We estimate that a significant number of units will be affected, yet at this stage, we cannot speculate regarding the specific figure.
"These products were marketed in the UK & a number of other countries over the past 11 years, so we would expect a fairly large number of them to be affected."
The warning came after an investigation by Whirlpool into dryers sold by Hotpoint & Indesit between April 2004 & September 2015. The US appliance giant acquired the Italian firm last year.