Two more homes caught alight in NSW this week thanks to faulty Samsung washing machines, more than 83,000 of which are potentially still in use across Australia.

Fire & Rescue NSW confirmed a house fire at a unit on Sainsbury Street in St Marys just before 9.00am on Friday.

The fire was extinguished by some tradespeople who were working in the building.

Another fire occurred just after 5.00pm on Wednesday at a house in William Street in Granville, which was put out by firefighters.

The fires are in addition to another blaze on Wednesday in Corlette.

Quick-thinking resident Jacquie Briskham turned off her mains power and contained the blaze with a garden hose before fire crew arrived.

Fire & Rescue NSW fire investigator, station officer Michael Forbes, urged anyone with a Samsung top loader washing machine to check their appliance "as a matter of priority".

"These products are typically left unattended while in use, so the risk to people and property if the machine fails is high," Mr Forbes said.

"If you notice any smoke or smell coming out of the washing machine, turn it off at the power point. If a fire does occur, get out, stay out and call Triple Zero (000)."

The three fires in NSW this week bring the total number caused by the faulty machines in the state to 20 since the April 2013 recall.

Five of the fires occurred within the last two months.

There have been 181 "incidents" nationwide as a result of the faulty machines, include over-heating, smoking or catching fire, according to Samsung.

However Fairfax Media believes these incidents may be under-reported as many state fire and emergency services do not record the detail of the brand of appliance that causes an electrical fire.

Samsung confirmed 83,686 machines out of nearly 150,000 sold across Australia have yet to be serviced to prevent the water leakage fault which can cause electrical fires.

The company is offering a free in-home service to rectify the issue.

NSW Fair Trading Minister Victor Dominello said the Australian Competition and Consumer Commission (ACCC) was responsible for monitoring the result of the national recall.

The ACCC said on Thursday it was "concerned" about the low take-up of Samsung's repair service.

Fairfax Media is awaiting additional comment from the ACCC as to whether it considers the result of the national recall to be adequate.

NSW Fair Trading is supporting the ACCC with its work.

Federal Consumer Affairs minister Bruce Billson is understood to be looking into the issue also.

Consumers who are concerned about their machine should contact Samsung's Product Safety Hotline on 1800 239 655 to arrange the free in-home service. The affected models are:

SW75V9WIP/XSA
SW65V9WIP/XSA
SW70SPWIP/XSA
SW80SPWIP/XSA
WA85GWGIP/XSA
WA85GWWIP/XSA