Do you live in an apartment? Then you regulate the temperature with your individual thermostat.

Do you live in a room? The heating works with a sensor. See below.

The heating in your complex is set to outside temperatures. 
This means the colder it is outside, the warmer the heating will get. In the spring and autumn when the days are relatively warm and the nights a bit colder, the system does not become very warm (yet). 

If it gets a bit colder during the day, your heating will get warmer. 
Is this not the case? Let us know. We will then see if there may be another cause. Does the radiator heat up locally (button side at the top)? There is a good chance that we will have to bleed the radiator. Please contact us for this.