Heating SystemsTypes of Heating SystemsEnergy SourcesCirculating Air SystemsSimple BasicsHeating Units - AirHeating Units (cont.)Water SystemsBoilersBoilers (cont.)Piping ConfigurationsSeries LoopOne Pipe SystemTwo Pipe – Reverse ReturnThree Pipe SystemFour Pipe SystemSteamSteam to Water Heat ExchangerRadiant SystemsNext TimeHeating SystemsHVAC 11aCNST 305 Environmental Systems 1Dr. Berryman11a Heating Systems; Fuels; Boilers; Furnaces; Hydronics, Radiant HeatChapter 5 (Toa)Types of Heating Systems    Energy SourcesCirculating Air SystemsHeat distributed by an air stream through a heating unit to supply ductsduct< 200’Must make good cost projections to assure an economical selectionSimple BasicsHeating Units - AirSplit System -w/ Gas FurnaceupflowdownflowhorizontalHeating Units (cont.)Single Packagew/ electric heatingWater SystemsHeat is distributed by a pumped water system though a heating unit to supply pipingboiler onboiler oncooling towercooling toweroffoffDifferent piping arrangements are used – Hydronic PipingBoilersWater Tube – Low Fire BoxGasses pass around tubes Responds quickly to load fluctuations.Types range from small (residential) to large (commercial)Water Tube – High Fire BoxBoilers (cont.)Piping ConfigurationsSeries LoopOne PipeTwo PipeThree PipeFour PipeOne pipe systemSeries LoopMaintenance or repair requires shutdownTemp control at each unit impossible# units limitedOnly heating or coolingOne Pipe SystemAllows for each unit to be controlledLimited # of units that can be servicedNeeds special fittingsOnly heating or coolingDiverting TeeTwo Pipe – Reverse ReturnEach unit fed by individual supply branchEach unit can be controlledFlow rates are balanced (heat or cool only)Three Pipe SystemSimilar to two pipe systemsAllows for simultaneous heating and coolingMixed returnProhibited by some energy codesFour Pipe SystemIt is actually 2- two pipe systemsAllows for simultaneous heating and coolingSeparate water return for heating and coolingMost efficientMost expensive – initial costSteamExpands 1000 its original stateCreates its own transport systemNo pumpsPiping configurations same for water – only at low pressures Operating temps 220 – 250oF About 15 pisgHigh Pressures (60 – 350 psig)Use heat exchangesNeed steam trapsSteam to Water Heat ExchangerCirculating pumpSteam in tubeWater in tubeRadiant SystemsFin-tube radiatorIron SectionalNext TimeBasics of Air Conditioning12 Cooling Systems; Refrigerants; Condenser/Evaporator Compressive; Absorption; Evaporative; Chillers; Heat SinksChapter 4