§ 50.090 HVAC.
   (A)   Exhaust fans.
      (1)   There shall be included in the equipment capsule two exhaust fans, flange mounted to the exhaust air piping as near the equipment capsule roof as is practical. Each fan capacity shall be 232 cfm at 0.2-inch static pressure (inches of water). Each fan shall feature a shaded pole motor with a squirrel cage blower. Each blower wheel shall be statically balanced to assure quiet performance and maximum air delivery. The fan motor will be complete with a conduit box. The exhaust fan shall operate on an independent 120-volt, single phase A.C. power source with single pole, 15-amp circuit breaker protection. Automatic control of the exhaust fan shall be by thermostat, air conditioning type (make on the rise) wired in parallel with a three-position maintained (H-O-A) selector switch located on the face of the main control panel. The exhaust fan control equipment shall be wall mounted in a receptacle box expressly designated for that purpose and in a location convenient for the use intended.
      (2)   The exhaust air piping system shall be size three inches and be welded through the roof and terminate at a point 16 inches above the roof. The cold air return piping system shall also be size three inches and on the exterior begin 16 inches above the capsule roof and terminate on the interior as near the equipment capsule floor as is practical. Both exterior air system pipes will be complete with white, PVC 180-degree return bends that are equipped with removable aluminum wire mesh insect screening. Exhaust and return air piping must be rigid and permanently fixed. Flexible, spiral wound or cloth ducts will not be accepted.
   (B)   Dehumidifier. A packaged dehumidifier with a sealed refrigeration type compressor rated at one- fifth horsepower, 4.7 full load amps and 430 watts shall be wall mounted within the equipment capsule in a manner that the condensate shall discharge to the sump through tubing provided for that purpose. The dehumidifier shall operate on a 120-volt, single phase A.C. power source and be provided with a safety protected power cord of UL approved three-wire construction with three-spade plug. The dehumidifier shall be capable of removing 27 pints of water in 24 hours when the room temperature is 80°F and at 60% relative humidity. (AHAM) Standard DH-1). The dehumidifier shall be actuated by a dial-controlled adjustable humidistat which will automatically cycle the unit at pre-selected moisture levels. The humidistat shall also have off and continuous run positions. The dehumidifier shall be listed by Underwriters Laboratories.
   (C)   Heater.
      (1)   The equipment capsule will be provided with an electric heater. The heater will have a rating of 3,000 watts, 10,240 BTU/HR output when operating on a 240-volt, single phase A.C. power source. The heater will be equipped with a 600 rpm low speed axial vane blower designed to deliver 175 cfm of down flow air and be driven by a four-pole motor. The heating element shall be of the sealed tubular type with a large parallel steel fins for quick heat transfer. The heater will be complete with a thermal overload cut-off and a built-in thermostat calibrated to provide a range of 55°F to 85°F.
      (2)   The heater shall be wall mounted, hard wired and complete with an individual 240-volt circuit, protected by a two-pole, 15-amp circuit breaker. The heater will be listed with Underwriters Laboratories, NEMA Standard 3-9-1967, HE2-2-02 Type I.
   (D)   Sump pump.
      (1)   One automatic submersible sump pump, with a rated capacity of ten gpm at 15 feet TDH shall be installed in the equipment capsule sump. The sump pump shall be complete with fractional horsepower motor, oil filled and hermetically sealed, designed to operate at 3,450 rpm, on a 120-volt, single-phase, A.C. power source and draw no more than 4.2 amps. A Buna-N shaft seal shall prohibit the pumped fluid from entering the motor housing. The pump body shall be constructed of aluminum and polypropylene and the motor casing shall be cast aluminum. The impeller shall be made of polypropylene plastic and affixed to a 304 grade stainless steel shaft. The sump pump will be clog-proof energy efficient design with built-in thermal protection. There shall also be included as an integral component of the pump a built-in check valve on the discharge. The sump pump shall operate within an approximate two and one-half-inch range turning on at approximately five inches and off at approximately two and one-half inches of depth in the sump. Therefore, the sump pump will initiate a pumping cycle before sump is filled.
      (2)   The sump pump discharge piping within the equipment capsule shall be size one and one- fourth inch to the coupling in the equipment capsule Schedule 40 PVC with solvent weld connections. The discharge piping system will be complete with a union connecting upper and lower halves of the discharge line. An optional dewatering drain system for freeze protection shall be designed into the sump pump discharge piping system. The dewatering line shall be included with the equipment and will be field installed, if required, by the start-up technician.
(Ord. passed 6-21-2011)