Carrier 50PEC09-18 specifications

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maximum speed. If the SAT continues to fall 5° F below the minimum SAT limit, all cooling stages will be disabled.

During Cooling mode, the reversing valve output will be held in the cooling position (either B or O type as configured) even after the compressor is stopped. The valve will not switch position until the Heating mode is required.

The configuration screens contain the minimum SAT parameter as well as cooling lockout based on outdoor-air temperature (OAT) Both can be adjusted to meet various specifications.

There is a 5-minute off time for the compressor as well as a 5-minute time delay when staging up to allow the SAT to achieve a stable temperature before energizing a second stage of capacity. Likewise, a 45-second delay is used when staging down.

After a compressor is staged off, it may be restarted again after a normal time-guard period of 5 minutes and if the sup- ply-air temperature has increased above the minimum supply- air temperature limit.

The WSHP Open controller provides a status input to moni- tor the compressor operation. The status is monitored to deter- mine if the compressor status matches the commanded state. This input is used to determine if a refrigerant safety switch or other safety device has tripped and caused the compressor to stop operating normally. If this should occur, an alarm will be generated to indicate the faulted compressor condition.

HEATING — The WSHP Open controller will operate one or two stages of compression to maintain the desired heating set point. The compressor outputs are controlled by the heating PI (proportional-integral) loop and heating stages capacity algo- rithm. They will be used to calculate the desired number of stages needed to satisfy the space by comparing the space tem- perature (SPT) to the appropriate heating set point. The follow- ing conditions must be true in order for the heating algorithm to run:

•Heating is set to Enable.

•Cooling mode is not active and the compressor time guard has expired.

•Condensate overflow input is normal.

•If occupied, the SPT is less than the occupied heating set point.

•Space temperature reading is valid.

•If unoccupied, the SPT is less than the unoccupied heat- ing set point.

•OAT (if available) is less than the heating lockout temperature.

If all the above conditions are met, the heating outputs will be energized as required, otherwise they will be deenergized. If the heating is active and should the SAT approach the maxi- mum SAT limit, the fan will be indexed to the next higher speed. Should this be insufficient, and the SAT rises further reaching the maximum heating SAT limit, the fan will be indexed to the maximum speed. If the SAT still continues to rise 5° F above the maximum limit, all heating stages will be disabled.

During Heating mode, the reversing valve output will be held in the heating position (either B or O type as configured) even after the compressor is stopped. The valve will not switch position until the Cooling mode is required.

The configuration screens contain the maximum SAT parameter as well as heating lockout based on outdoor-air temperature (OAT); both can be adjusted to meet various specifications.

There is a 5-minute off time for the compressor as well as a 5-minute time delay when staging up to allow the SAT to achieve a stable temperature before energizing a second stage of capacity. Likewise, a 45-second delay is used when staging down.

After a compressor is staged off, it may be restarted again after a normal time-guard period of 5 minutes and if the sup- ply-air temperature has fallen below the maximum supply air temperature limit.

The WSHP Open controller provides a status input to moni- tor the compressor operation. The status is monitored to deter- mine if the compressor status matches the commanded state. This input is used to determine if a refrigerant safety switch or other safety device has tripped and caused the compressor to stop operating normally. If this should occur, an alarm will be generated to indicate the faulted compressor condition. Also, if auxiliary heat is available (see below), the auxiliary heat will operate to replace the reverse cycle heating and maintain the space temperature as required.

AUXILIARY HEAT — The WSHP Open controller can con- trol a two-position, modulating water, or steam valve connect- ed to a coil on the discharge side of the unit and supplied by a boiler or a single-stage ducted electric heater in order to main- tain the desired heating set point. Should the compressor capac- ity be insufficient or a compressor failure occurs, the auxiliary heat will be used. Unless the compressor fails, the auxiliary heat will only operate to supplement the heat provided by the compressor if the space temperature falls more than one degree below the desired heating set point (the amount is config- urable). The heat will be controlled so the SAT will not exceed the maximum heating SAT limit.

Auxiliary Modulating Hot Water/Steam Heating Reheat

—The control can modulate a hot water or steam valve con- nected to a coil on the discharge side of the unit and supplied by a boiler in order to maintain the desired heating set point should the compressor capacity be insufficient or a compressor failure occurs. Unless a compressor fault condition exists, the valve will only operate to supplement the heat provided by the compressor if the space temperature falls more than one degree below the desired heating set point. The valve will be con- trolled so the SAT will not exceed the maximum heating SAT limit.

Two-Position Hot Water/Steam Heating Reheat — The con- trol can operate a two-position, NO or NC, hot water or steam valve connected to a coil on the discharge side of the unit and supplied by a boiler in order to maintain the desired heating set point should the compressor capacity be insufficient or a com- pressor failure occurs. Unless a compressor fault condition ex- ists, the valve will only open to supplement the heat provided by the compressor if the space temperature falls more than one degree below the desired heating set point. The valve will be controlled so the SAT will not exceed the maximum heating SAT limit. The heat stage will also be subject to a 2-minute minimum OFF time to prevent excessive valve cycling.

Single Stage Electric Auxiliary Heat — The control can op- erate a field-installed single stage of electric heat installed on the discharge side of the unit in order to maintain the desired heating set point should the compressor capacity be insufficient or a compressor failure occurs. Unless a compressor fault con- dition exists, the heat stage will only operate to supplement the heat provided by the compressor if the space temperature falls more than one degree below the desired heating set point. The heat stage will be controlled so the SAT will not exceed the maximum heating SAT limit. The heat stage will also be sub- ject to a 2-minute minimum OFF time to prevent excessive cycling.

INDOOR AIR QUALITY (IAQ) AND DEMAND CON- TROLLED VENTILATION (DCV) — If the optional in- door air quality sensor is installed, the WSHP Open controller can maintain indoor air quality via a modulating OA damper providing demand controlled ventilation. The control operates the modulating OA damper during occupied periods. The con- trol monitors the CO2 level and compares it to the configured set points, adjusting the ventilation rate as required. The control provides proportional ventilation to meet the requirements of

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Contents Contents Safety ConsiderationsInstallation General50PEC Physical Data Condensate OUTWater OUT A50-8335A50-8337 Water22.2 OD A50-8338A50-8339 Damper Opening50PEC18 Bottom Return Cabinet Dimensions Right Hand Piping 50PEC09-15 Bottom Return Cabinet Dimensions Left Hand Piping 50PEC18 Bottom Return Cabinet Dimensions Left Hand Piping 50PEC09-15 Front Return Cabinet Dimensions Right Hand Piping 50PEC18 Front Return Cabinet Dimensions Right Hand Piping 50PEC09-15 Front Return Cabinet Dimensions Left Hand Piping A50-834550PEC18 Front Return Cabinet Dimensions Left Hand Piping A50-8347 50PEC09-15 Chassis Dimensions Front Return Optional Autoflow Valve MotorizedOptional Motorized Optional FusedOptional Disconnect Box Autoflow Water Valve Optional Autoflow50PEC18 Chassis Dimensions Front Return Wire Electrical Connections Mount UnitA50-8452 09-18A50-8327.eps A50-8328 Sensor, Water Coil Freeze ProtectionNight Low Limit Switch A50-8329Return Air Sensor Blower Motor Wiring NLL PremierLink Controller Applications with Complete C Control A50-8355 A50 8354LWT 8353 A50-8380 Wshp Open ControlA50-7467tf Wire Low Voltage ConnectionsElectrical Data 50PEC Units A50-8441Recommended Thermostat Wire Sizes Field-Supplied Sensors for Wshp Open ControllerSPT Sensors Rnet Wiring Install Supply and Return PipingRnet Wiring Specifications A50-8443PRE-START-UP Temporary Connection for Flushing System PipingMin Entering Air Rated Entering Air, dry bulb/wet bulb Air and Water LimitsMin Ambient Air Rated Ambient Air Max Ambient Air Max Entering Air, dry bulb/wet bulbWater Quality Guidelines DIP Switch Block S2 Accessory 1 Relay Options Complete C Control Jumper Settings See , 18,Deluxe D Control Jumper Settings See , 20, Field Selectable InputsUnit Start-Up/Cooling DIP Switch Block S2 Accessory 2 Relay OptionsSTART-UP Operating LimitsUnit Start-Up with Wshp Open Controls BACview6 Display InterfaceCoaxial Water Pressure Drop GPMOperation Approximate Fluid Volume gal Per 100 ft of PipeAntifreeze Percentages by Volume Units with Aquazone Complete C ControlUnits with Wshp Open Multiple Protocol Page Complete C and Deluxe D Board System Test Complete C Control LED Code and Fault Descriptions Aquazone Deluxe D Control LED IndicaService Gravity Flow Method Air Coil Fan Motor Removal TroubleshootingRefrigerant Charging Replacing the Wshp Open Controller’s BatTroubleshooting Fault Heating Cooling Possible Cause SolutionUnit Does Not Operate Status Appendix a Wshp Open Screen ConfigurationAlarm Status SensorSystem Settings Appendix a Wshp Open Screen ConfigurationMaintenance ConfigurationOptimal Start ScheduleAppendix a Wshp Screen Open Configuration ServiceTest Configuration Service Point Name Password Editable Range Default LevelHigh Alarm Limit AlarmPage Page Copyright 2009 Carrier Corporation 50PEC Unit START-UP Checklist II. START-UPA50-8453 Heating Cycle AnalysisCooling Cycle Analysis A50-8454
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