More than a dozen people were injured, and many were displaced after the incident, just months after the building was inspected for quality-of-life concerns.
Plainfield officials say that an electrical fault or a lithium-ion battery may have been the cause of the fire.
Neighbors who live in 35 of the 42 apartments of the twin buildings were left to spend the night inside - with no heat.
The city, they were told, has no place to put them.
Seven apartments were damaged by smoke, flames or water. Additionally, tenants have been getting by with space heaters because they claim there has been no heat for weeks since temperatures began to fall.
One renter, Sahari Castro, is seven months pregnant and lives in a basement apartment. She moved in eight months ago.
"People have been saying there's no heat since last summer, or that there is not even a boiler," said Castro to Eyewitness News. "Since I moved in, I haven't had the heat on once."
An inspector with DCA's Bureau of Housing Inspection was at the property Tuesday morning and found an inoperable boiler that provides heat to the entire building.
The Bureau issued an imminent hazard violation for lack or hot water with an abatement date of 12/6/23.
A team of Bureau inspectors will be reinspecting the property on Friday.
The next-door building has been condemned since August, as Eyewitness News previously reported.
Castro says her apartment is not livable.
"It's just wet everywhere. Beds are wet, everything is wet," she said about her apartment. "It's hard because there's nowhere to go."
What would she say to the landlord?
Two words: "help us."
"There were seven apartments affected," said Castro. "Help us. Instead of just throwing us to the curb. Where are we supposed to go?"
----------
* Get Eyewitness News Delivered
* More New Jersey news
* Send us a news tip
* Download the abc7NY app for breaking news alerts
* Follow us on YouTube