Felix – I never cease to amazed by circumstances such as yours; like where was your Strata Manager when the E/C was making decisions that it doesn’t have the authority to make, and for that matter how were other Owners permitted to add air-conditioners to the Common Property without an enabling Special By-Law setting-out installation procedures and making them (and not the O/C) responsible for the on-going maintenance and repair of those?
So it’s that Special By-Law (SBL) which needs to be put in place, by the inclusion of a suitable Motion on the Agenda of the next General Meeting to Register that together with Conditions that mirror the installation methods that your O/C is satisfied with such as the concealment of the pipework within the wall cavity, and to also grant retrospective approval to those air-conditioners that have already been installed on the proviso that the Owners concerned agree in writing to themselves maintain those.
With regard to the most recent air-conditioner installation, try to ascertain if the scope-of-work that the E/C improperly approved was what was then undertaken by the Lot Owner.
If your O/C’s lucky and it’s not, say with regard to the visible pipework or in fact any other discrepancy, then your O/C needs to advise that Owner in writing that a proposal to create and Register a SBL covering the proper installation of air-conditioners will be on the Agenda of the next General Meeting, and if passed, they’ll be required to at their cost make their installation complaint.
If your O/C’s unlucky, then I’m afraid that the letter (above) would still need to be issued, with an amendment to the affect that should the SBL render their installation non-complaint, then the O/C will (at its cost) make all necessary alterations to achieve that compliance.
Maybe not the answer you’re after, but I’m afraid they’re the consequences of improperly managing a Strata Plan!