Dear colleagues alualo and servimat: the combination circuit does not work for what you ask because if the two bathrooms are occupied you will have problems 1- enter bathroom 1 turn on the extractor 2- Enter bathroom 2 and turn on the extractor but as it is already on and it is a combined circuit the effect will be the opposite .... turn it off. He realizes the error and turns it on again 3- Bath 1 leaves the extractor and does not know that in bathroom 2 they are specifying it .... that is what you want to avoid 4 leave the bathroom 2 and it would not be surprising that by reflex they give the key and turn it on so they will have to turn it off again The simplest solution is what was said first ... 2 switches in parallel but the opposite of that is that if someone forgets to turn it off you have to go through both bathrooms to check and turn it off To avoid this it can be automated but it will turn on every time someone enters the bathroom even if it does not require it. regards