SMTP using nodemailer in nodejs without GMail

I am using node mailer with GMail

smtpTransport = nodemailer.createTransport("SMTP", {
    service: "Gmail",
    auth: {
        user: "myemail ",
        pass: "mypass"
    }
});

which is working fine, but I want to use my own email server instead of GMail.

This:

smtpTransport = nodemailer.createTransport("SMTP", {
    service: "mymailservr link url",
    port : 25
    auth: {
        user: "myemail ",
        pass: "mypass"
    }
});

It throws this error:

connect ECONNREFUSED