Rheem Marathon Point-of-Use Series Use and Care Manual - Page 4

Introduction Thank you for buying your non-metallic electric water heater. Your new water heater is made of the latest materials and will not rust or corrode. It will give many years of hot water service when installed, operated and maintained according to the instructions in this manual. Your water heater is completely assembled and ready to install. This manual provides the general instructions for installation. Because of several variables, such as the installation location, existing piping, and local codes, it is impossible to provide exact instructions for everyone's specific needs. For this reason, it is suggested that the entire manual be read prior to beginning any installation work, then carefully plan the installation. This can help to avoid costly mistakes including damage to the water heater, not covered under terms of the warranty. Almost all new products (automobiles, boats, clothing, plastic and wood items, etc.) have an odor or smell to them for a time. This water heater may also have a "new" smell or odor to it due to the non-metallic materials used in the manufacturing process. This "new" smell is not harmful, and will disappear in a short time. The vacuum valve, which must be used when installing the water heater, is factory installed. The location chosen for the water heater must take into consideration the following: LOCAL INSTALLATION REGULATIONS This water heater must be installed in accordance with these instructions, local codes, utility company requirements or, in the absence of local codes, the latest edition of the National Electrical Code. It is available from some local libraries or can be purchased from the National Fire Prevention Association, Batterymarch Park, Quincy, MA 02269 as booklet ANSI/NFPA 70. LOCATION Locate the water heater in a clean dry area as near as practical to the area of greatest heated water demand. Long uninsulated hot water lines can waste energy and water. Place the water heater in such a manner that the thermostat and element access panels can be removed to permit inspection and servicing B A A - Diameter of water heater plus 2" min. B - Maximum 2" To open drain, line should be at least 3/4" ID and pitched for proper drainage. Figure 1. - Auxiliary Drain Pan such as removal of elements or checking controls. The water heater and water lines should be protected from freezing temperatures. Do not install the water heater in outdoor, unprotected areas, or near any other appliances where high temperature are present, such as wood burning stoves, boilers or furnaces. High temperatures can warp or otherwise damage the non-metallic construction of this water heater. ! CAUTION The water heater should not be located in an area where leakage of the tank or connections will result in damage to the area adjacent to it or to lower floors of the structure. Where such areas cannot be avoided, it is recommended that a suitable drain pan, adequately drained, be installed under the water heater. NOTE: Auxiliary drain pan installation MUST conform to local codes. Drain Pan Kits are available at your local retail outlet or service center. Installation 1. INSPECT SHIPMENT - Inspect water heater for possible damage. Check the markings on the rating plate of the water heater to be certain the power supply corresponds to that for which the water heater is equipped. 2. THERMAL EXPANSION - Determine if a check valve exists in the inlet water line. It may have been installed in the cold water line as a separate back flow preventer, or it may be part of a pressure reducing valve, water meter or water softener. A check valve located in the cold water inlet line can cause what is referred to as a "closed water system". A cold water inlet line with no check valve or back flow prevention device is referred to as an "open" water system. As water is heated, it expands in volume and creates an increase in the pressure within the water system. This action is referred to as "thermal expansion". In an "open" water system, expanding water which exceeds the capacity of the water heater flows back into the city main where the pressure is easily dissipated. A "closed water system", however, prevents the expanding water from flowing back into the main supply line, and the result 2 of "thermal expansion" can create a rapid, and dangerous pressure increase in the water heater and system piping. This rapid pressure increase can quickly reach the safety setting of the relief valve, causing it to operate during each heating cycle. Thermal expansion, and the resulting rapid, and repeated expansion and contraction of components in the water heater and piping system can cause premature failure of the relief valve, and possibly the heater itself. Replacing the relief valve will not correct the problem! The suggested method of controlling thermal expansion is to install an expansion tank in the cold water line between the water heater and the check valve. The expansion tank is designed with an air cushion built in that compresses as the system pressure increases, thereby relieving the over pressure condition and eliminating the repeated operation of the relief valve. Other methods of controlling thermal expansion are also available. Contact your installing contractor, water supplier, or plumbing inspector for additional information regarding this subject.