The Model K Mystery (2020)
heatinghelp.com
heatinghelp.com
https://www.amazon.com/radiator-key/s?k=radiator+key
Over the years, air can collect in the radiator, and it keeps hot water from flowing through it. Radiators will have a little square screw valve near their top, and you use the key to bleed the air out. Voila! The radiator will get hot.
https://www.bloomberg.com/news/articles/2020-08-05/the-curio...
The article talks about co-ops but most of those Co-op buildings were originally rent controlled or rent stabilized. The management had no incentive to fix anything ever, and neither did the tenants since they didn't have actual equity in the apartment. This led to the apartments having appliances and fixtures that seemed to be from the 1940s.
At least the rooms were really big, none of these buildings at the time were renovated to increase the number of Apartments per floor.
We lived on the top floor and often we would have leaks from the flat roof after snow storms. One time my mother took a bucket of snow and dumped it on the doorstep of the superintendent who had refused to do anything about our complaints.
Fun times!
Cheap out on this labor and you will pay for it many times over.