Five people have died since the start of June in house fires, a toll already higher than last year's total.

So far firefighters have attended 202 house fires across NSW with 42 per cent of those homes not having a working smoke alarm and another 16 per cent without one entirely.

Fire and Rescue NSW deputy commissioner Megan Stiffler reminded people that firefighters can check a household's smoke alarms and replace them at no cost.

"It's also a great opportunity to ask for advice from the experts on how you can keep yourself and your family warm but safe," she said.

"Our firefighters are dedicated to protecting the irreplaceable but it's important everyone takes steps to safeguard their homes from the threat of fire, especially during winter."

Three of the five fatalities are still under investigation with investigators finding a faulty fridge behind the deaths of an elderly couple earlier this month.

Emergency Services Minister Steph Cooke said there was a simple precaution that people could take to keep themselves safe: having a working smoke alarm.

"Fire can engulf a home in a matter of minutes and while smoke won't wake you up, a smoke alarm will, which could be the difference between life and death," she said.

Australian Associated Press