Ian David Moller, 82, was critically injured when his Stokes Valley flat was set alight in November, and died four days later.
It was the third arson at the Hanson Grove block of flats within a month.
The first took place on October 10, another on October 14, and the third, after which Moller died, on November 5. All of the fires started during the early hours of the morning.
Three men, aged in their 20s and 30s, were charged with murder and arson, while a fourth man in his 20s was accused only of arson.
They pleaded not guilty to all charges in the High Court at Wellington, and have been able to keep their names secret until a suppression hearing in October.
Moller's niece, Denise Harrison, earlier told RNZ her family was "heartbroken" Moller had died in such tragic circumstances.
"He was a very quiet man who went to church and spent time with his friends and he was never a bother to anybody," she said.
"So to have his life ended so tragically is just completely heartbreaking for all of us."
