Carrier 50PTH, PTV specifications Units with Modulating Hot Water Reheat HWR Option

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Boilerless Changeover Temperature — Switch 8 on S1 provides 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 BANK 2 (S2) — This set of DIP switches is used to configure accessory relay options. See Fig. 16, 18, 20, 22, and 23.

Switches 1 to 3 — These DIP switches provide selection of Accessory 1 relay options. See Table 15A for DIP switch combinations.

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

Table 15A — 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

Reheat — Humidistat

Off

Off

Off

Reheat — Dehumidistat

Off

On

Off

LEGEND

NSB — Night Setback

OAD — Outside Air Damper

NOTE: All other DIP switch combinations are invalid.

Table 15B — DIP Switch Block S2 —

Accessory 2 Relay Options

ACCESSORY 2

DIP SWITCH POSITION

RELAY OPTIONS

4

5

6

Cycle with Compressor

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.

Factory Setting — Switch 8 is set to ON. Do not change the switch to OFF unless instructed to do so by the factory.

Units with Modulating Hot Water Reheat (HWR) Option

STANDALONE — NO DDC CONTROLS — 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 any other water source heat

pump. The reversing valve ("O" signal) is energized in cool- ing, along with the compressor 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

WSHP OPEN CONTROLS — A heat pump equipped with the hot water reheat option and the WSHP Open controller, operates in three modes: Cooling, Heating and Dehumidifica- tion. Cooling and Heating modes follow the standard water source heat pump operation with the reversing valve control- ling the operating mode (Heating or Cooling) and the compres- sor.

The hot water reheat option uses the Deluxe D board and the optional humidity sensor to provide dehumidification oper- ation that is separate from the standard heating or cooling cy- cle. The Dehumidification mode is active when the value of the humidity sensor exceeds the appropriate (occupied or unoccu- pied) humidity setpoint in the WSHP Open controller. When this occurs, the WSHP Open controller outputs a signal to the H terminal of the Deluxe D board which starts dehumidifica- tion with hot water reheat. The WSHP Open controller also sets the fan to operate at the airflow defined by the medium fan speed and the tap setting of SW3 and SW4. Dehumidification is ONLY active when neither cooling nor heating is required and the humidity sensor value exceeds the humidity setpoint. Also, both the HWR option and the Optional RH sensor must be set to Enable in the WSHP Open control for dehumidifica- tion.

HWR APPLICATION CONSIDERATIONS — Unlike most hot gas reheat options, the HWR option will operate 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

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Contents Safety Considerations ContentsGeneral InstallationPhysical Data 50PTH, PTV, PTD026-072 Units 50PTH026-072 Dimensional Data Aux Electric Heat Disconnect Typical Installation 50PTH Unit50PTV Dimensional Data 50PTD Dimensional Data Back Discharge Side DischargeMove to Side Install Condensate DrainMount the Unit RotateTrap Condensate Drain Horizontal Unit PitchDrains field-installed Typical Ground-Water Piping InstallationWater Quality Guidelines Wire Field Power SupplyMetal Hose Minimum Bend Radii 50PTH,PTV,PTD Electrical Data Sensor, Water Coil Freeze Protection Alarm Relay ContactsTrans RVSECM BM ECM Alarm Relay Contacts Discharge Temp Switch Relay/Contactor Coil A50-8363 8364 A50SPT LWTWshp Open Control A50-8571Field-Supplied Sensors for Wshp Open Controller Rnet Wiring SpecificationsSPT Sensors A50-8443 Wire Field ControlsRnet Wiring Wire TerminalA50-8442 A50-8141A50-7764tf A50-8441CFM Adjust Settings Cooling SettingsDehumidificaton Mode Settings Heating SettingsBlower Performance Data Wshp Open Fan Only / Low Fan and Med Fan Airflow PRE-START-UPWshp Open High Fan Airflow Deluxe D Control Jumper Settings Complete C Control Jumper SettingsField Selectable Inputs Units with Modulating Hot Water Reheat HWR Option DIP Switch Block S2 Accessory 1 Relay OptionsDIP Switch Block S2 Accessory 2 Relay Options Humidistat/Dehumidistat Logic Deluxe D DIP Switch SettingsHWR Operating Modes Mode Input OutputOperating Limits 50PTH, PTV, PTD Units START-UPOperating Limits A50-8145 Water OutUnit Start-Up Heating Mode Unit Start-Up Cooling ModeWater Temperature Change Through Heat Exchanger Suction Discharge Super Sub Water Air Temp A50-8444 Unit Start-Up with Wshp Open Controls026 038 049 Unit 50PTH, PTV Water Temperature F GPMCoaxial Water Pressure Drop PTDUnits with Aquazone Complete C Control Approximate Fluid Volume gal Per 100 Ft of PipeAntifreeze Percentages by Volume OperationUnits with Wshp Open Multiple Protocol Page Page Complete C and Deluxe D Board System Test Complete C Control LED Code Fault DescriptionsLED Status Description of Operation Alarm Relay LED Fault Description CodeAquazone Deluxe D Control LED Indica Alarm RelayService Replacing the Wshp Open Controller’s Bat TroubleshootingRefrigerant Charging Air Coil Fan Motor RemovalKOhm 60.0 50.0 90.080.0 70.0Page Fault Description Solution ECM TroubleshootingA50-8448 ECM Pin ConnectorsA50-8447 ECM Troubleshooting Flow DiagramFault Heating Cooling Possible Cause Solution Wshp TroubleshootingGood Practices Performance Monitor Code 7 Auto ResettingNo Fault Code Shown Over/Under VoltageLow Discharge Air Temperature in HeatingHigh Head Pressure Low Suction PressureSensor Appendix a Wshp Open Screen ConfigurationAlarm Status StatusConfiguration Appendix a Wshp Open Screen ConfigurationMaintenance System SettingsSchedule Service Appendix a Wshp Screen Open ConfigurationTest Point Name Password Editable Range Default Level Configuration ServiceScreen Name Alarm Page Page Copyright 2010 Carrier Corporation II. START-UP 50PTH,PTV,PTD START-UP ChecklistA50-8450 Heating Cycle AnalysisCooling Cycle Analysis A50-8449
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