19SAFETY PRECAUTIONSElectric workBefore starting to use the system, read carefully this "SAFETY PRECAUTIONS" to ensure a properoperation of the system.Safety precautions described here are classified as " WARNING" and " CAUTION". Precau-tions which are shown in the column of " WARNING" means that an improper handling could lead toa grave result like a death,serious injury, etc. However, even if precautions are shown in the col-umn of " CAUTION", a very serious problem could occur depending on situation. Make sure toobserve these safety precautions faithfully because they are very important information to ensure thesafety.Symbols which appear frequently in the text have following meanings.The electric work must be burden on the authorized engineer with qualification for electricwork and grounding work, and the work must be conducted in accordance with electric equip-ment technical standard.The power source for the unit is to be of exclusive use.An earth leakage breaker should be installed. (This is necessary to prevent electricshock.)The unit must be grounded.CAUTIONS FOR INSTALLATIONWhen you have read through the manual, keep it always at hand for ready consultation. If the opera-tor is replaced, make sure to hand over this manual to the new operator.Strictly prohibited. Observe instructionsfaithfully.Provide a positivegrounding.WARNINGThe system should be applied toplaces as office , restaurant,residence and the like.The system should be installedby your dealer or a professionalinstaller.When you need some optional devicessuch as a humidifier, electric heater,etc., be sure to use the productswhich are recommended by us. Thesedevices should be attached by a pro-fessional installer.Application to inferior environmentsuch as an engineering shop,couldcause equipment malfunction and seri-ous injury or death.Installation by yourself is not encour-aged because it could cause such prob-lems as water leakage, electrical shockor fire accident by some improper han-dling.Installation by yourself is not encour-aged because it could cause such prob-lems as water leakage, electrical shockor fire accident by some improper han-dling.