Manuals / Carrier / Household Appliance / Air Conditioner

Carrier 37HS specifications

Models: 37HS

1 84

Download 84 pages 16.18 Kb

Page 60

VAV HEATING AND COOLING WITH SYSTEM- POWERED CHANGEOVER Ð This application uses a CV control package along with a wall-mounted thermostat pack- age (cooling/heating) and a system-powered changeover con- trol package. The cooling thermostat is direct acting (DA) while the heating thermostat is reverse acting (RA).

Fig. 61 Ð Location of CV Unit for Warm-Up Application

VAV HEATING AND COOLING WITH SYSTEM- POWERED CHANGEOVER Ð This application uses a CV control package along with a wall-mounted thermostat pack- age (cooling/heating) and a system-powered changeover con- trol package. The cooling thermostat is direct acting (DA) while the heating thermostat is reverse acting (RA).

Operation is very similar to system-powered warm-up. The changeover switch assembly is ®eld installed in the unit ple- num and is piped in-line between the volume controller and the thermostat. It consists of 2 thermally operated pneumatic valves, one for each thermostat. The tube from the volume controller is connected by a `T' into the valve assembly,

making control air available to each valve. The valve for the DA cooling thermostat is normally open as long as there is cool supply air in the plenum (Fig. 62). The other valve is normally open when warm air is being supplied, matching the RA heating thermostat (Fig. 63). Each valve is con- nected to the corresponding thermostat by a separate tube. In the cooling mode (Fig. 64), the cooling valve is open, activating the cooling thermostat, while the heating thermo- stat is isolated by the closed heating valve. On changeover from cooling to heating, the cooling valve closes and the heating valve opens, shifting control to the heating thermo- stat (Fig. 65).

60

Image 60

Carrier 37HS specifications

Contents

37HS Moduline Air Terminals Step 1 Ð Determine Air Volume CfmSystem-PoweredControls With System-PoweredControls WithBUILDING LOAD CALCULATION Fig. 2 Ð 37HS Unit With VAV ControlsFig. 3 Ð Estimating Block Load Fig. 4 Ð Floor Plan of Typical Zonesfor Single-StoryOffice Building DESIGN PROCEDURE with example Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page ·Baseboard ·Overhead air Fig. 6 Ð 35BD Heating Slot Boot Diffuser Fig. 5 Ð Separate Duct Heating SystemPerformance Heating Ð Downblow Slot Fig. 7 Ð Director Diffuser TERMINAL SELECTION AND LAYOUT Table 1 Ð Optimum Outlet DischargeTable 2 Ð Location Guidelines Fig. 9 Ð Single Moduline Unit Connected to Supply DuctFig. 10 Ð Moduline Units in Air Series Fig. 11 Ð Master Unit and Slave UnitsStep 2 Ð Lay Out Terminals Table 3 Ð Recommended Maximum Cfm Per TerminalFig. 14 Ð Diffuser Locations for Preferred 2-Wayor One-WayBlowFig. 16 Ð Locate Units to Prevent Down-Drafts Table 4 Ð Air Throw Data Ð1-Wayand 2-WayBlow, 2-SlotDiffusers Table 5 Ð Air Throw Data ÐStep 3 Ð Consider Unit Combinations And Run Fig. 17 Ð Staggered UnitsFig. 18 Ð Unit Spacing Fig. 19 Ð Run-OutDuct for Single Moduline Unit Table 6 Ð 37HS1 Units in Air Series Table 6 Ð 37HS1 Units in Air Series cont Table 7 Ð 37HS2 Units in Air Series Table 7 Ð 37HS2 Units in Air Series cont Table 8 Ð 37HS4 Units in Air SeriesTable 8 Ð 37HS4 Units in Air Series cont Table 9 Ð Maximum Cfm Through the Inlet Collar of a Single Unit or of Units in Air Series0.97+ 0.16 = 1.13 in. wg Master Unit Ð Units with System-Powered Table 10 Ð Minimum Static Pressure at ControlControls and Standard Diffusers Fig. 23 Ð Three 37HS2 ModulineFig. 25 Ð Flexible Duct Used with 90-DegreeBend Table 13 Ð Maximum Number of Units in anAir Series on One Controller Fig. 26 Ð Air Intake on Master UnitFig. 27 Ð Location of Volume Controller on Single UnitPage Fig. 30 Ð Corrected Layout Fig. 31 Ð Control Tubing ConnectionThe corrected layout 1.Room A has its own controllerTHE MODULINE VALVE Fig. 32 Ð Bellows and Unit Air Valve Arrangement UNIT SHUTOFF Ð BELLOWS FULLY INFLATEDUNIT MODULATING Ð BELLOWS PARTIALLY INFLATED UNIT FULL CAPACITY Ð BELLOWS DEFLATEDFig. 33 Ð Cross Section of 37HS Moduline Air Terminal Fig. 34 Ð Bellows ComparisonSystem-PoweredControls CONTROL APPLICATIONSFig. 35 Ð High and Low Pressure Pick-UpTubes Fig. 36 Ð 37HS Control Components Fig. 37 Ð Basic 37HS Control OperationFig. 39 Ð 37HS Air¯ow Volume Controller Fig. 42 Ð Diffuser Baffle AssemblyFig. 41 Ð Wall-MountedThermostat Fig. 38 Ð 37HS Control Filter/ManifoldFig. 43 Ð Constant Volume Control Arrangement System-Powered Warm-UpFig. 44 Ð Variable Air Volume Control Arrangement Fig. 45 Ð VAV Control Arrangement forFig. 47 Ð Cooling/Heating Wall Thermostat Fig. 48 Ð Wall-MountedHeating ThermostatFig. 49 Ð VAV Control Arrangement for Electric Warm-UpPneumatic Warm-UpSwitch Fig. 51 Ð VAV Control Arrangement withElectric Heat Interlock Fig. 52 Ð Pilot Valve for Pneumatic SequencedCONTROL SELECTION Table 14 Ð Control IndexTable 15 Ð 37HS Control Combinations Table 15 Ð 37HS Control Combinations cont Table 15 Ð 37HS Control Combinations cont CONTROLTable 15 Ð 37HS Control Combinations cont CONTROLSystem-PoweredControls CONTROL OPERATING SEQUENCESFig. 55 Ð Variable Volume Controls Schematic Unit Supplying Air Controller Shut Off, Unit Shut Off Controller Bleeding, Unit Heating VAV HEATING AND COOLING WITH SYSTEM- POWERED CHANGEOVER Ð This application uses a CV control package along with a wall-mountedthermostat pack- age cooling/heating and a system-poweredchangeover con- trol package. The cooling thermostat is direct acting DA while the heating thermostat is reverse acting RA Fig. 62 Ð Heating/Cooling Unit Ð Cooling, Cold Air in Duct, Changeover in Cooling Fig. 64 Ð Heating/Cooling Unit Ð Cooling, Cold Air in Duct, Changeover in Cooling VAV HEATING Ð It is suggested that the following section be reviewed before reading this section: VAV Cooling, page System-PoweredControls with Electric Interface Controller Bleeding, Unit Heating VAV HEATING AND COOLING WITH ELECTRIC CHANGEOVER Ð This application uses a CV control pack- age along with a wall-mountedthermostat package cooling/ heating and an electric changeover package. The change- over valve permits control of the unit to be switched between the cooling and heating sides of a cooling/heating thermo- stat. It is eld-installed in-linebetween the volume control- ler and the thermostat Fig. 71 Ð Heating/Cooling Unit Ð Heating, Hot Air in Duct, Electric Changeover in Heating Fig. 74 Ð Connection for Electric Interlock Fig. 75 Ð Piping Diagram, Heating/Cooling Fig. 76 Ð Sequence Diagram Ð DA ThermostatFig. 77 Ð Piping Diagram, Heating/Cooling Fig. 78 Ð Sequence Diagram, RA ThermostatFig. 79 Ð Piping Diagram, NO Conguration Warm-UpSwitchFig. 81 Ð Piping Diagram, NC Conguration LEGEND FOR FIG. 79 -AIRFLOW ADJUSTMENT CFM HK08ZZ030Table 17 Ð Multiple Unit Air¯ow Variation AIR DISTRIBUTION Fig. 86 Ð Typical Room Air Distribution Pattern 37HS Ð 2-WAYBLOW 37HS2 Ð ONE-WAYBLOWPage Table 18 Ð Standard Diffusers for 37HS1 Table 19 Ð Standard Diffusers for 37HS2 Table 20 Ð Standard Diffusers for 37HS4 Table 21 Ð Optional Diffusers for 37HS1 Table 22 Ð Optional Diffusers for 37HS2 Table 23 Ð Optional Diffusers for 37HS4 Table 24 Ð Air Throw Data Ð 1-Wayand 2-WayBlow, 2-SlotDiffusersTable 25 Ð Air Throw Data Ð 2-Wayand 1-WayDirector, 3-SlotDiffusersPage Copyright 1991 Carrier Corporation