Carrier RHR, RVS, RDS006-060, RVR, RVC, RHS, 50RHC DIP Switch Block S2 Accessory 1 Relay Options, Oad

Page 31

boilerless operation mode, only the compressor is used for heating when FP1 is above the boilerless changeover tempera- ture set by switch 8 below. Select ON for normal operation or select OFF for boilerless operation.

Boilerless Changeover Temperature — Switch 8 on S1 pro- vides selection of boilerless changeover temperature set point. Select OFF for set point of 50 F or select ON for set point of 40 F.

If switch 8 is set for 50 F, then the compressor will be used for heating as long as the FP1 is above 50 F. The compressor will not be used for heating when the FP1 is below 50 F and the compressor will operates in emergency heat mode, staging on EH1 and EH2 to provide heat. If a thermal switch is being used instead of the FP1 thermistor, only the compressor will be used for heating mode when the FP1 terminals are closed. If the FP1 terminals are open, the compressor is not used and the control goes into emergency heat mode.

DIP SWITCH BLOCK 2 (S2) — This set of DIP switches is used to configure accessory relay options. See Fig. 20.

Switches 1 to 3 — These DIP switches provide selection of Accessory 1 relay options. See Table 14 for DIP switch combinations.

Switches 4 to 6 — These DIP switches provide selection of Accessory 2 relay options. See Table 15 for DIP switch combinations.

Table 14 — DIP Switch Block S2 —

Accessory 1 Relay Options

ACCESSORY 1

DIP SWITCH POSITION

RELAY OPTIONS

1

2

3

Cycle with Fan

On

On

On

Digital NSB

Off

On

On

Water Valve — Slow Opening

On

Off

On

OAD

On

On

Off

LEGEND

 

 

 

NSB — Night Setback

OAD — Outside Air Damper

NOTE: All other DIP switch combinations are invalid.

Table 15 — DIP Switch Block S2 —

Accessory 2 Relay Options

ACCESSORY 2

DIP SWITCH POSITION

RELAY OPTIONS

4

5

6

Cycle with Fan

On

On

On

Digital NSB

Off

On

On

Water Valve — Slow Opening

On

Off

On

OAD

On

On

Off

LEGEND

 

 

 

NSB — Night Setback

OAD — Outside Air Damper

NOTE: All other switch combinations are invalid.

Auto Dehumidification Mode or High Fan Mode — Switch 7 provides selection of auto dehumidification fan mode or high fan mode. In auto dehumidification fan mode the fan speed relay will remain off during cooling stage 2 if terminal H is active. In high fan mode, the fan enable and fan speed relays will turn on when terminal H is active. Set the switch to ON for auto dehumidification fan mode or to OFF for high fan mode.

Switch 8 — Not used.

Units with Modulating Hot Water Reheat (HWR) Option — A heat pump equipped with Hot Water Reheat (HWR) can operate in three modes: cooling, cooling with reheat, and heating. The cooling and heating modes are like other Aquazone™ water source heat pumps. The reversing

valve ("O" signal) is energized in cooling, along with the com- pressor contactor(s) and blower relay. In the heating mode, the reversing valve is deenergized. Almost any thermostat will activate the heat pump in heating or cooling modes. The Deluxe D microprocessor board, which is standard with the HWR option, will accept either heat pump (Y,O) thermostats or non-heat pump (Y,W) thermostats.

The reheat mode requires either a separate humidistat/ dehumidistat or a thermostat that has an integrated dehumidifi- cation function for activation. The Deluxe D board is config- ured to work with either a humidistat or dehumidistat input to terminal “H” (DIP switch settings for the Deluxe D board are shown in Table 16). Upon receiving an “H” input, the Deluxe D board will activate the cooling mode and engage reheat.

Table 16 — Humidistat/Dehumidistat Logic and

Deluxe D DIP Switch Settings

Sensor

2.1

2.2

2.3

Logic

Reheat

Reheat

(ON) - H

(OFF) - H

 

 

 

 

 

Humidistat

Off

Off

Off

Reverse

0 VAC

24 VAC

Dehumidistat

Off

On

Off

Standard

24 VAC

0 VAC

Table 17 shows the relationship between thermostat input signals and unit operation. There are four operational inputs for single stage units and six operational inputs for dual stage units:

Fan Only

Cooling Stage 1

Cooling Stage 2

Heating Stage 1

Heating Stage 2

Reheat Mode

MODULATING HWR APPLICATION CONSIDER- ATIONS — Unlike most hot gas reheat options, the mod- ulating HWR option (RVC,RHS,RVS,RDS only) will oper- ate over a wide range of entering-water temperatures (EWTs). Special flow regulation (water regulating valve) is not required for low EWT conditions. However, below 55 F, supply-air temperatures cannot be maintained at 72 F because the cooling capacity exceeds the reheat coil capac- ity at low water temperatures. Below 55 F, essentially all water is diverted to the reheat coil (no heat of rejection to the building loop). Although the HWR option will work fine with low EWTs, overcooling of the space may result with well water systems or, on rare occasions, with ground loop (geothermal) systems (NOTE: Extended range units are required for well water and ground loop systems). Since dehumidification is generally only required in cooling, most ground loop systems will not experience overcooling of the supply-air temperature. If overcooling of the space is a con- cern (e.g., computer room well water application), auxiliary heating may be required to maintain space temperature when the unit is operating in the dehumidification mode. Water source heat pumps with HWR should not be used as makeup air units. These applications should use equipment specifically designed for makeup air.

HWR COMPONENT FUNCTIONS — The proportional controller operates on 24 VAC power supply and automatically adjusts the water valve based on the supply-air sensor. The supply-air sensor senses supply-air temperature at the blower inlet, providing the input signal necessary for the proportional control to drive the motorized valve during the reheat mode of operation. The motorized valve is a proportional actuator/three- way valve combination used to divert the condenser water from the coax to the hydronic reheat coil during the reheat mode of operation. The proportional controller sends a signal to the motorized valve based on the supply-air temperature reading from the supply air sensor.

The loop pump circulates condenser water through the hy- dronic reheat coil during the reheat mode of operation (refer to Fig. 28). In this application, the loop pump is only energized

31

Image 31
Contents Safety Considerations ContentsGeneral InstallationPage PSC FAN Motor and Blower Physical Data Aquazone 50RHC,RVC006-060 UnitsPhysical Data Aquazone 50RHS,RVS,RDS015-070 Units Physical Data Aquazone 50RHR,RVR006-060 UnitsPermanent Split Capacitor Code Return Discharge Airflow ConfigurationRight 030 Ext Power Cond Therm Supply ReturnDepth Height Out Pump Supply Ensate 015-024Right Back Back RightTypical Installation 50RHC,RHR,RHS Units Right Top TopView Configuration Top View-Left ReturnConfiguration Left Return Left View IsometricFront View Configuration Left Return Left View Air Coil OpeningIsometric View CodeFront-View Ht Return/Bottom DischargeReturn/Bottom Discharge Isometric View Top ViewMove to Side Remove ScrewsSide Discharge Rotate50RHS Units Mounting the Unit50RHC Units 50RHR UnitsHorizontal Unit Pitch Condensate DrainCondition Acceptable Level Field Control Wiring Field Power Supply WiringCompr LOCBMC NECRVS Typical Aquazone Deluxe D Control WiringLON HpwsTrans A50-8154 Low Voltage Field Wiring RLA 50RHC,RVC Electrical DataRLA LRA Motor Unit Circuit FUSE/HACR FLARLA LRA FUSE/HACR 50RHR,RVR VOLTS-PHASE Voltage Compressor FAN Total MIN MAX50RHR,RVR Electrical Data Unit Circuit Units50RDS, RHS, RVS Electrical Data PRE-START-UP50RHR,RVR Rated MIN FAN 50RHR,RVR Blower PerformanceSpeed 50RHC,RVC Rated MIN FAN 50RHC,RVC Blower Performance50RVC Blower Performance with Hot Water Reheat HWR Option Reheat External Static Pressure ESP Loss Coil Face Velocity50RHS,RVS,RDS Rated FAN 50RVC Blower Performance with Wet Coil50RHS,RVS,RDS Blower Performance Coil Face Velocity WET Coil ReductionCoil Face 50RHS, RVS with Reheat ESP Loss Control Jumper Settings See FigField Selectable Inputs 50RHS, RVS Blower Performance with HWRAccessory DIP Switch Position Relay Options DIP Switch Block S2 Accessory 1 Relay OptionsDIP Switch Block S2 Accessory 2 Relay Options Humidistat/Dehumidistat Logic Deluxe D DIP Switch SettingsOutput Control Accessory Relay ConfigurationsSTART-UP HWR Operating ModesOperating Limits 50RHC,RVC Units Unit Start-Up Cooling ModeWater Temperature Change Through Heat Exchanger Operating LimitsTemp F TON Unit Start-Up Heating ModeTypical Unit Operating Pressures and Temperatures Entering Cooling Heating Water GPM50RHS,RVS,RDS Coaxial Water Pressure Drop 50RHR,RVR Coaxial Water Pressure Drop50RHC,RVC Coaxial Water Pressure Drop Units with Aquazone Complete C Control Approximate Fluid Volume gal Per 100 Ft of PipeAntifreeze Percentages by Volume OperationUnits with HWR Option Complete C Control LED Code Fault DescriptionsSystem Test Aquazone Deluxe D Control LED Indica ServiceESD Gravity Flow Method Refrigerant Charging TroubleshootingAir Coil Fan Motor Removal Fault Heating Cooling Possible Cause Solution TroubleshootingUnit Does Not Operate II. START-UP 50RHC,RVC,RHR,RHS,RVR,RVS,RDS START-UP ChecklistCooling Cycle Analysis Heating Cycle Analysis