MPs have demanded Whirlpool must explain steps taken to address a supposed safety risk affecting up to one million faulty tumble dryers in the UK.
In January the Government's Business, Energy and Industrial Strategy Committee said the firm needed to take urgent action to address problems that have led to at least 750 fires since 2004.
This includes the death of two men killed in a fire in Llanwrst, North Wales, which a coroner's report ruled was caused by a faulty door mechanism on a Whirlpool tumble dryer.
The firm pledged to resolve issues with the defective machines within one week of the initial January report.
Rachel Reeves MP, chairwoman of the Business, Energy and Industrial Strategy Committee, said: "Whirlpool's initial response to the discovery of defects in their tumble dryers was woeful.
"Following our report, Whirlpool pledged to resolve the risk from faulty machines within a week of being contacted. Whirlpool must spell out how many cases they have resolved since this pledge and show that real progress is being made to address these serious safety concerns."
In a letter to Whirlpool's brand and communications director, Ian Moverley, Ms Reeves asks how many faulty machines have been resolved within the target period and what steps are being taken to contact affected customers.
The letter also asks for information on any problems identified with modified tumble dryers.
The firm - which has set up an online checker tool for affected models - previously told the BEIS Committee they would share their response to certain fatal incidents, which the committee is now calling for them to disclose as soon as possible.
Ms Reeves added: "We would encourage anyone who is still worried about their tumble dryer to get in touch with Whirlpool so they can make them safe and put an end to the unacceptable situation where machines are acting as potential fire hazards in people's homes.
"We are concerned to hear of safety problems with modified tumble dryers. We would like to know the extent of this problem and what steps Whirlpool are taking to address it.
"Whirlpool should also set out how they will deal with a separate fault, involving the door mechanisms of some of their tumble dryers, which has been linked to a tragic case in Llanwrst."