If you haven't set a system-wide email configuration, you are unable to use the password recovery feature - you can preserve your settings if you are comfortable browsing and editing a sqlite database.
http://sqlitebrowser.org/ - this tool will allow you to open and browse/edit the database. Turn off webapp via ssh - (sudo /etc/init.d/gunicorn stop) then download /opt/alarmdecoder-webapp/instance/db.sqlite and open with the downloaded db browser. Open up the user's table, and empty out the password field for the specified user. Re-upload the db.sqlite and restart gunicorn process. You should be able to login with a blank password and then reset your password.
If you aren't comfortable doing this, then you will have to remove the database and set up the webapp again.
Not an employee of the company. Just here to help and keep things clean.