Lennox International Inc Dave Lennox Signature Collection XP17 System HEAT PUMPS Unit Start−Up

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Servicing Units Delivered Void of Charge

If the outdoor unit is void of refrigerant, clean the system using the procedure described below.

1.Leak check system using procedure outlined on page 18.

2.Evacuate the system using procedure outlined on page 19.

3.Use nitrogen to break the vacuum and install a new filter drier in the system.

4.Evacuate the system again using procedure outlined on page 19.

5.Weigh in refrigerant using procedure outlined in figure 21.

6.Monitor the system to determine the amount of moisture remaining in the oil. It may be necessary to replace the filter drier several times to achieve the required dryness level. If system dryness is not verified, the compressor will fail in the future.

3.After evacuation is complete, open both the liquid and vapor line service valves to release the refrigerant charge contained in outdoor unit into the system.

4.Replace the stem caps and tighten to the value listed in table 1.

5.Check voltage supply at the disconnect switch. The voltage must be within the range listed on the unit’s nameplate. If not, do not start the equipment until you have consulted with the power company and the voltage condition has been corrected.

6.Set the thermostat for a cooling demand. Turn on power to the indoor indoor unit and close the outdoor unit disconnect switch to start the unit.

7.Recheck voltage while the unit is running. Power must be within range shown on the nameplate.

8.Check system for sufficient refrigerant by using the procedures listed under System Refrigerant.

Unit Start−Up

IMPORTANT

If unit is equipped with a crankcase heater, it should be energized 24 hours before unit start−up to prevent compressor damage as a result of slugging.

1.Rotate fan to check for binding.

2.Inspect all factory− and field−installed wiring for loose connections.

System Refrigerant

This section outlines procedures for:

1.Connecting gauge set for testing and charging (see figure 19.

2.Checking and adjusting indoor airflow as described in figure 20.

3.Add or remove refrigerant using the weigh in method provided in figure 21, and verifying charge using subcooling method described in figure 22.

GAUGE SET

CONNECTIONS FOR TESTING AND CHARGING

MANIFOLD GAUGE SET

LOW HIGH

B TRUE SUCTION PORT

CONNECTION

 

REFRIGERANT TANK

 

CHARGE IN

A

 

LIQUID PHASE

 

 

 

DIGITAL SCALE

INSIDE OUTDOOR UNIT

 

C

D

 

TO LIQUID

 

LINE SERVICE

TEMPERATURE

 

VALVE

SENSOR

 

 

OUTDOOR UNIT

TEMPERATURE SENSOR

(LIQUID LINE)

AClose manifold gauge set valves and connect the center hose to a cylinder of HFC−410A. Set for liquid phase charging. BConnect the manifold gauge set’s low pressure side to the true suction port.

CConnect the manifold gauge set’s high pressure side to the liquid line service port.

DPosition temperature sensor on liquid line near liquid line service port.

Figure 19. Gauge Set Connections

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XP17 SERIES

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Contents Table of Contents GeneralHeat Pumps Base with Elongated Legs Unit Dimensions −− Inches mmSide View Access View Model Number IdentificationControl BOX Typical Unit Parts ArrangementUsing Manifold Gauge Set Operating Service ValvesShipping and Packing List Reinstall Stem Cap Operating Angle Type Service ValveOperating Ball Type Service Valve To Access Service Port2CONNECT Manifold Gauge SET Recovering Refrigerant from Existing System1DISCONNECT Power Recovering RefrigerantUnit Placement Placement, Slab Mounting and Stabilizing Unit Detail a Outside Unit PlacementRemoving and Installing Panels Stabilizing Unit on Uneven SurfacesRoof Mounting Detail D Detail a Louvered Panel InstallationLouvered Panel Removal Detail CRefrigerant Line SET New or Replacement Line SetRefrigerant Line SET Alling Horizontal Runs Refrigerant Line SET From Vertical to HorizontalBrazing Connections 2CAP and Core Removal 1PIPING Panel Removal and Preparing Line SET7PREPARATION for Next Step Wrap Service ValvesFlow Nitrogen Braze Line SETFlushing Line Set and Indoor Coil Flushing Line Set and Indoor CoilEqualizer Line Installation Installing Indoor Expansion ValveIndoor Expansion Valve Installation Sensing Bulb InstallationLeak Test Leak Test Line Set and Indoor CoilS S S S Evacuating Line Set and Indoor Coil24VAC Transformer Size Circuit and Install Disconnect2INSTALL Thermostat Electrical3A. Route Control Wires Ting Route Control Wires Ting4ROUTE High Voltage and Ground Wires Typical XP17 Wiring Heat Pump Control AGE Heat Pump Control A175 Jumpers and TerminalsHeat Pump Control A175 Jumper and Terminal Descriptions Flat metal jumper Field Control WiringFurnace Control System Refrigerant Connections for Testing and ChargingServicing Units Delivered Void of Charge Unit Start−UpAirflowindoor Coil Cooling Mode Indoor Airflow CheckHeating Mode Indoor Airflow Check Adding or Removing RefrigerantSubcooling Charging Method Using HFC−410A Weigh In MethodAir Handler / Coil Match ups and Targeted Subcooling Values Psig Operating and Temperature PressuresDefrost System System OperationsUnit Sensors Resistor Location Sensor Temperature / Resistance RangeYES Defrost Calibration Sequence of OperationsS S Test Pin E33 FunctionsOr below Low Pressure S87 Switch OperationHigh Pressure Switch S4 Sequence of Operation Input Fault or Miswire Degrees Resistance Fahrenheit 136.3 2680 DS15 and DS13 Ault Lockout LED Codes System Status, Fault and Lockout LED CodesDS11 and DS14 ATUS, Fault Lockout LED Codes Resetting Fault and Lockout LED CodesModerate Device Alert Status225ºF 107ºC Lockout Vice removed or Clears after FAN Motor Control A177 OPERATION, Field Configuration and TestingTroubleshooting FAN Motor B4 Test ProcedureFan Motor Control Flash and Pause Durations Fan Motor Control Error/Fault LED CodesFan Motor Control Stage LED Indicator Codes Fan Motor Control RPM, LED Code and DC Voltage OutputDemand Begins TOP Grille or FAN Motor Mount Adjustment for FAN ClearanceTOP Grille Adjustment FAN Motor Position AdjustmentFAN Motor Control A177 PULSE−WIDTH Modulation PWM Testing for External Power to Fan Motor Control Finish StripStart TerminalSnow Guard Top Cover MaintenanceHomeowner SunSource Home Energy System START−UP Checks XP17 Start−Up and Performance ChecklistCooling Mode Heating Mode