Whirlpool, the manufacturer of household appliances, is accused of putting customers in danger by giving out incorrect advice about tumble dryers that could catch fire, according to Which?, the consumer group.
In February the company announced that up to five million of its products in the UK could be affected by a fault that has led several to catch fire.
It wrote to almost four million customers about the problem but, ten months on, almost a quarter of affected customers are still waiting for a repair or replacement.
The Which? survey also found that a third of customers who have had their dryers repaired or replaced were dissatisfied with the way that the company had handled the situation.
More than a quarter of customers were