Carrier 50HQP072-120 TROUBLESHOOTING, Thermistor , Contr ol Sensors

30

TROUBLESHOOTING

When troubleshooting problems with a WSHP, see

Table 18.

Thermistor — A thermistor may be required for single-

phase units where starting the unit is a problem due to low

voltage. See Fig. 26 for thermistor nominal resistance.

Control Sensors — The control system employs 2 nom-

inal 10,000 ohm thermistors (FP1 and FP2) that are used for

freeze protection. Be sure FP1 is located in the discharge fluid

and FP2 is located in the air discharge. See Fig. 27.

Fig. 26 — Thermistor Nominal Resistance

0.0

10.0

20.0

30.0

40.0

50.0

60.0

70.0

80.0

90.0

-17.7 -6.6 4.4 15.6 26.7 37.848.9 60.0

Temperature (C)

Resistance (kOhm)

a50-8163

LEGEND

Fig. 27 — FP1 and FP2 Thermistor Location

COAX — Coaxial Heat Exchanger

Airflow

Refrigerant Liquid Line Flow

SUCTIO N

COMPRESSOR

DISCHARGE

COAX

EXP ANSION

VA LV E

FP 2 FP 1

LIQUI D

LIN E WA TER IN WA TER OUT

CONDENSA TE

OVERFLO W

(CO)

AIR COI L

FREEZ E

PROTECTIO N

WA TE R

COI L

PROTECTIO N

THERMIST OR

( °C) ( °C)

AI R

COI L

AIRFLOW AIRFLO W

Contents

Main Installation, Start-Up, and Service Instructions CONTENTS SAFETY CONSIDERATIONS AQUAZONE 50HQP072-120 Horizontal Water Source Heat Pumps with PURON Refrigerant (R-410A) 50 Hz GENERAL INSTALLATION Step 1 Check Jobsite Step 2 Chec k Unit Page a50-8531 Fig. 1 Unit Dimensions Step 3 Locate Unit Step 4 Mount Unit Step 5 Install Duct System Step 6 Install Condensate Piping Drain Step 7 Field Con ver t Air Dischar ge Step 8 Install Piping Connections Step 9 Install Field Power Supply Wiring Page Table 2 Water Quality Guidelines Fig. 12 50HQP072-120 Units Typical Control Wiring with Complete C Control Page Fig. 14 Premierlink Controller Applications Wiring with Complete C Control LEGEND NOTE: Reversing valve is on in Cooling mode. Fig. 15 Premierlink Controller Applications Wiring with Deluxe D Control LEGEND NOTE: Reversing valve is on in Cooling mode. Table 3A Electrical Data 50HQP072-120 Standard Units POWER BLOCK Step 10 Install Field Control Wiring PRE-START-UP System Chec kout Airflow and External Static Pressure Table 5 Blower Data 50HQP072 a50-8544 Table 6 Blower Data 50HQP096 Table 7 Blower Data 50HQP120 FIELD SELECTABLE INPUTS Complete C Control Jumper Settings (See Fig. 12) Complete C Control DIP Switches Deluxe D Control Jumper Settings (See Fig. 13) Deluxe D Contr ol DIP Switches Deluxe D Control Accessory Relay Configura- tions START-UP Operating Limits Air Coil Cleaning Start Up System Scr oll Compressor Rotation Unit Start-Up in Heating Mode Flow Regulati on Flushing Antifreeze Cooling T o wer/Boiler Systems Ground Coupled, Closed Loop and Plateframe Heat Exchanger W ell Systems OPERATION P o wer Up Mode Units with Aquazone Complete C Control SYSTEM TEST Te s t M o d e Retry Mode Aquazone Deluxe D Control LED Indica- tors SERVICE Filter s W ater Coil Condensate Drain P ans Refrigerant System Condensate Drain Cleaning Compressor Fan M ot ors Belt Air Coil Checkin g System Char ge Blower F an P erformance Adjustment TROUBLESHOOTING Thermistor Contr ol Sensors Table 18 Troubleshooting Table 18 Troubleshooting (cont) Page Page Page HEATING CYCLE ANALYSIS COOLING CYCLE ANALYSIS *Use 500 for water, 485 for antifreeze. (kW)