Classes with a lot of lines of code are generally bad.
Too many responsibilities, low cohesion, or both.
However, sometimes it is not possible to make functions smaller. Reasons could be various.
What can be done in this circumstance?
This article describes a way of implementing Strategy design pattern using a database-based runtime configuration. The approach allows to dynamically (re)configure class behavior without requiring code-based rearrangements.
I released on GitHub a PHP library for querying and editing data on the Tado Thermostat System.
It is integrated in Laravel 5.x for quick setup in this excellent framework.