The mistake was quickly corrected while the trucks were enroute on Saturday. It's not clear whether it was a factor in the deaths.
A spokesman for Mayor Michael Bloomberg acknowledged the dispatch error, but said other issues were more significant.
Jason Post said the basement windows were barred and the floors were illegally subdivided. He said the building also lacked working smoke detectors.
Some firefighters cited the incident as a sign that the city's new dispatching system is not working. City officials defended the system, which was put in place over union objections.