Oh dear,DV as well! We purchased from RyF at another development and had simialr experiences. Some A/C units have in fact never worked since completion. If you have 18 trouble free months you are very lucky. RyF will do absolutely nothing. You will spend vast amountys of time money and energy chasing them and then waiting for a response , They will ask all other owners on your development to lodge their complaints and stil will do nothing. AEA will ask you to e-mail your complaints and still nothing will be done. Finally in perhaps another 12 months. They will say it is the responsibilty of individual owners.
You will be much better of biting the bullet and having a new system installed. The one you have will be the cheapest possible and will have been badly installed. You may find like we did that the gas in your system is being phased out and has been banned by the EU. Individual types of gas cannnot be mixed with others (a bit like petrol and diesel) and as all the pipework was put in before your celilngs were installed - guess what you will have to have dirty great holes cut in your celings throughout your apartment to install a new one.
The various options are;-
Go to Carrefour and buy some mobile stand alone units - cost about 500 euros each. Pay for a complete new system , cost between 4000 and 7000 euros depending upon the size of your apartment. Abandon the system installed and have a new system of completelty different design with wall mounted units- cost 2500 euros.
I have the numbers of just about every a/c engineer and various companies in the area. If you meed any info please pm me.