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OC Sportsplex Pool HVAC Unit Replacement <br />PDC Project 23022 Pool Dehumidification Unit 23 84 16 - 4 <br />tube manifolds. Coating surface shall have superior hardness characteristics of 2H per ASTM <br />D3363 and a cross-hatch adhesion of 4B-5B per ASTM B3359.Impact resistance shall be up to <br />100 in/lb per ASTM D2794.Humidity and water immersion resistance shall be up to a minimum <br />1000 and 250 hours respectively (ASTM D1735 and ASTM D870).Corrosion durability shall be <br />confirmed through testing to no less than 3,000 hours salt spray per ASTM B117 using scribed <br />aluminum test coupons.The coil shall maintain hydrophilic properties without degradation of the <br />top coat for a minimum of 1000 hours per ASTM G85 Annex 4. <br />C.All tubes shall be expanded into fin collars.All joints shall be brazed.The coil shall be tested to <br />500 PSIG while submerged in water.All brazing shall be done with nitrogen gas inside tubes to <br />give clean internal surfaces.The coil shall be dried and sealed.Inside of tubes shall be <br />commercially free of oxides and foreign matter. <br />D.The coil shall be sectioned to provide proportional air-to-refrigerant latent and sensible heat <br />removal capacity.This capacity modulation shall be accomplished by utilizing multiple thermal <br />expansion valves (TXV)for the evaporator.Each TXV shall be equipped with a refrigerant flow <br />control solenoid valve and refrigerant sight glass. <br />2.07 CONDENSER COIL (AIR REHEAT COIL) <br />A.Condenser coil shall be capable of rejecting all heat (100%)recovered from the compressor and <br />evaporator.Refer to equipment schedule for required MBH of reheat coil capacity. <br />B.Coil shall be Electro-GuardTM corrosion resistance Electro coated fins.Coil shall have a flexible, <br />epoxy polymer,E-coated in a total submersion bath,uniformly applied to all coil surface area <br />without material bridging between fins.Coating process shall ensure complete coil encapsulation <br />and a uniform dry film thickness from 0.5-1.5 mil on all surface areas including fin edges,end <br />plates,structural frames,“u”bends and headers.Coating surface shall have superior hardness <br />characteristics of 2H per ASTM D3363 and across-hatch adhesion of 4B-5B per ASTM B3359. <br />Impact resistance shall be up to 100 in/lb per ASTM D2794.Humidity and water immersion <br />resistance shall be up to a minimum 1000 and 250 hours respectively (ASTM D1735 and ASTM <br />D870).Corrosion durability shall be confirmed through testing to no less than 3,000 hours salt <br />spray per ASTM B117 using scribed aluminum test coupons. <br />C.All tubes shall be expanded into fin collars.All joints shall be brazed.The coil shall be tested to <br />600 PSIG while submerged in water.All brazing shall be done with nitrogen gas inside tubes to <br />give clean internal surfaces.The coil shall be dried and sealed.Inside of tubes shall be <br />commercially free of oxides and foreign matter. <br />2.08 HEAT RECOVERY COILS <br />A.The unit shall have heat recovery between the minimum exhaust and outdoor air streams per <br />specifications <br />1.The heat recovery coils shall be sized for heat transfer between the two air streams <br />2.The heat recovery fluid circulating between coils shall be glycol.The module shall be a <br />complete package and independent circuit that includes a circulating pump,fill valves and <br />expansion tank <br />B.Coils shall be fully dipped and coated with a polyester/enamel coating for maximum corrosion <br />protection.Coating shall comply with ASTM B117/D1654 and ASTM D2126 for corrosion <br />resistance against common acids,salt and gases <br />C.Aluminum fin and copper tube joints mechanically bonded to assure high heat transfer <br />D.Plate heat recovery that will add fan horsepower and therefore have a negative effect on energy <br />saving are not acceptable.Strategies that use the main compressors to cool exhaust air to try and <br />act as heat recovery cannot be used in place of full time heat recovery because the compressors <br />will not be running in the coldest months requiring heat recovery the most. <br />2.09 HO <br />A.Modulating (0-10V)auxiliary air heat control by means of a factory mounted and wired three-way <br />control valve <br />Docusign Envelope ID: D4F3B98E-0756-4A0C-A3AD-05AA32D39F1C