York H5CE150A50 Installation Manual

Contents

292424-XIM-A-030712 Unitary Products Group6. Is the control circuit transformer set for the proper volt-age?7. Have the fuses, disconnect switch and power wire beensized properly?8. Are all compressor hold-down nuts properly secured?9. Are any refrigerant lines touching each other or anysheet metal surface? Rubbing due to vibration couldcause a refrigerant leak.10. Are there any visible signs of a refrigerant leak, such asoil residue?11. Is any electrical wire laying against a hot refrigerant line?INITIAL START-UP1. Supply power to the unit through the disconnect switchat least 8 hours prior to starting the compressor.2. Move the system switch on the thermostat to the AUTOor COOL position.3. Reduce the setting of the room thermostat to energizethe compressor.4. Check the operation of the evaporator unit per the manu-facturer's recommendations.5. With an ammeter, check the compressor amps againstthe unit data plate.6. Check for refrigerant leaks.7. Check for any abnormal noises and/or vibrations, andmake the necessary adjustments to correct (e.g. fanblade(s) touching shroud, refrigerant lines hitting onsheet metal, etc.)8. After the unit has been operating for several minutes,shut off the main power supply at the disconnect switchand inspect all factory wiring connections and bolted sur-faces for tightness.OPERATIONNOTE: The timing intervals described in the following pro-cedures are nominal. Some variations will naturallyoccur due to differences in individual components,or due to variations in ambient temperature or line/control voltage. Refer to the wiring labels inside ofthe unit control access panel for additional informa-tion.SEQUENCE OF OPERATIONOVERVIEWThese series of condensing units, come factory equippedwith Simplicity™ controls to moni tor all unit functionality andsafety controls.SAFETY CONTROLSThe Simplicity™ control board incorporates features to moni -tor safety circuits as well as minimize compressor wear anddamage. An anti-short cycle delay (ASCD) is utilized to pre-vent operation of a compressor too soon after its previousrun. Additionally, a minimum run time is imposed anytime acompressor is energized to allow proper oil return to the com-pressor. The ASCD is initiated on unit start-up and on anycompressor reset or lockout.The Simplicity™ control board monitors the following inputsfor each cooling system:• A high-pressure switch is factory installed to protectagainst excessive discharge pressure due to ablocked condenser coil or a condenser fan motorfailure. During cooling operation, if a high-pressurelimit switch opens, the Simplicity™ control board willde-energize the associated compressors and initiatethe 5-minute ASCD. If the call for cool is still presentat the end of the ASCD, the control board will re-energize the halted compressor.• If a high-pressure switch opens three times withintwo hours of operation, the Simplicity™ controlboard will lockout the associated system compres-sors and will flash an error code (see Table 9 ).• A low-pressure switch to protect the unit againstexcessively low suction pressure is standard on allcondensing units.If the low-pressure switch opens during normal operation, theSimplicity™ control board will de-energize the compressor,initiate the ASCD, and shut down the condenser fans.On startup, if the low-pressure switch opens, the Simplicity™control board will monitor the low-pressure switch to makesure it closes within one minute. If it fails to close, the unit willshut down the associated compressor and begin an ASCD. Ifthe call for cool is still present at the end of the anti-shortcycle time delay, the control board will re-energize the haltedcompressor.If a low-pressure switch opens three times within one hourof operation, the Simplicity™ control b oard will lock-out theassociated compressor and flash an error code (see Table9 ).An ambient air switch will lock out mechanical cooling at 45°F(7°C). In order to operate the unit in ambient temperaturesbelow 45°F (7°C), the optional low ambient kit must be fieldinstalled which will allow the unit to operate during conditionsdown to 0°F (18°C).PUMP OUT OPTIONThe pump out option is field installed on 15 and 20 ton sys-tems. The pump out circuit is activated each time the first and