The heater does not heat.

hello guys, i have a 1999 model peugeot 306 car

First of all, welcome to us. There are two possibilities, either the heater radiator is blocked. or hot cold adjustment flap is faulty.

Hodja, first of all, stop by the places that provide cleaning and try your luck. You are lucky if it opens with cleaning. Unfortunately, it goes until the replacement of the heater core.