INSTALLATION INSTRUCTIONS: IMPORTANT: Be sure to follow the assembly instructions before proceeding. It is recommended that installation of the whole house water filter be done by a professional plumber since cutting into your home's main water line is required. Both the sediment prefilter and the main filter have 1” NTP fittings. Use Teflon tape only on fittings. The sediment prefilter is the first thing the water passes through, then the main filter unit. Be sure to note inlet and outlet markings on both units. It is recommended that a three-valve by-pass valve be installed to loop the entire system. This enables bypassing the water for lawn watering and makes servicing easier. Union connections on either side of the main tank should be considered – they would make tank change-outs much easier. After the unit is installed, it is necessary to flush the unit thoroughly. Do this at the nearest water faucet (such as a utility sink or outdoor faucet). The water will be blackish in color for some time - this is normal carbon dust. Continue to run water until it runs clear. Shut the water off and let the unit sit for a while, then flush it again. The homeowner may notice an initial "cloudy" appearance to the water for a day or so - this cloudiness is actually tiny air bubbles being purged from the carbon. This is normal, harmless, and will clear up in a day or two.