Assessments - 2, GPA: 3.5
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Check all parts for any damage in transit. The carrier is responsible for the condition of the heater package upon arrival. If damage is apparent, note the freight bill accordingly. This will support your claim with the freight carrier. 2. Check the nameplate on the enclosure and verify that the heaters and the control panel are rated for the correct voltage. 3. Check the watt rating on each element and verify the sum of all elements is equal to the KW rating as ordered. 4. The control panel is nameplated for the maximum amperage that the panel can safely control and may be equal to or greater than the actual amperage required for your heater package. See Installation Instructions on page 5 to calculate amperage required. / Introduction / The purpose of a basin heater is to prevent water freezing in the cooling tower basin during periods of shutdown or standby operation. The heater system is sized according to tower model and location to give maximum protection against water freezing in the cold water basin. This heating system is not intended to protect the tower fill and other components from icing. Refer to Marley Technical Bulletin # H-002 "Operating Cooling Towers in Freezing Weather." Contact your Marley Sales Representative for a copy of this publication. The Marley basin heater system is manufactured by INDEECO, a leader in immersion heating equipment. The system is referred to as a "heater package" and consists of immersion heaters, a control panel and combination temperature / liquid level sensor with a 12'-0" cable length. The basic control panel contains a contactor(s) of sufficient capacity for the heater elements selected. In addition the panel contains a transformer to reduce line voltage to 24VAC for panel control power, and a solid state relay card to detect low temperature and low water conditions. The panel enclosure is rated NEMA 4X (liquid tight, noncorrosive) and the sensor cable is UL outdoor rated. The sensor probe is stainless steel with 1.2" NPT threads and a PVC bulkhead fitting for installation in the cold water basin. The panel may control more than one heating element, up to its nameplate KW rating for the voltage and phase stated. In addition to the components of the basic panel described above, available options are fusing, circuit breakers or disconnect switches. The circuit diagram located on the inside of the panel cover will indicate the panel configuration. Warning Caution Note The following defined terms are used throughout this manual to bring attention to the presence of hazards of various risk levels, or to important information concerning the life of the product. Indicates presence of a hazard which can cause severe personal injury, death or substantial property damage if ignored. Indicates presence of a hazard which will or can cause personal injury or property damage if ignored. Indicates special instructions on installation, operation or maintenance which are important but not related to personal injury hazards. / Installation / For detailed information concerning installation, refer to the heater Note installation drawing provided with the cooling tower. Heater Element Install the heater element(s) in the depressed area of the cold water basin near the outlet. Provide clearance of 7.8" or more above the floor. A single centrally located heater can protect up to 300 square feet of basin surface area from ice damage. To protect larger surface areas, position several heaters so they protect equal areas. For multicell towers, no more than two cells may be protected by a single heater package. For three or more cells additional heater packages are necessary. The heater should never operate out of the water. It would become Caution extremely hot (1500°F) and destroy the heater element and/or ignite nearby combustible materials. As a precaution and to prevent fires when the clearance between any part of a heater element and combustible materials is less than 10", install a sheet metal shield to reflect and dissipate the heat. The shield must not contact the heater element and should extend beyond the heater element in all directions as shown in Table 1. Table 1 Heater Clearance inches 1 2 4 6 8 10 Shield Extension inches 10 9 7 4 2 0 Heater Supports Install metal supports for the heater element where necessary to keep the unsupported length under 30". The number of supports required is as shown in Table 2. Table 2 Heater Kilowatts 1 -9 12-18 Number of Supports None 1 / Installation / Control Panel The control panel is suitable for outdoor mounting, and may be mounted on the tower, but not inside the tower. Wire the heaters to the panel. Wire the panel to the branch circuit supplying power to the heater. The field supplied branch circuit disconnect switch and the branch circuit protective device (fusing or circuit breaker) shall be sized in accordance with the NEC/CEC rules for actual load. The total heater load can be calculated as shown below. If the heater control pa...