How does Heroku limit the request size?

Question

I'm trying to submit a form with a file to Node+Express server. I set the bodyParser limit to 5M:

app.use(express.bodyParser({ limit: '5mb' }));

It works fine on local machine. However on Heroku I get "Request Entity Too Large" error for files larger than 1M.

How does Heroku put this limit and how it can be changed?

EDIT: The actual error is generated by the nginx and not the node app:

Answer 1

I forgot to post the resolution. The problem was only for that app. I tried to create a new app and it worked fine. So I think it was related to the specific server instance that the initial application was using. On another instance the problem didn't exist.