Carrier AquaForce 30XQ0502 Installation, Operation & Maintenance Instructions Manual

Contents

40 Carrier Yileng - Shanghai, China8.3 - High-pressure safety switch30XQ units are equipped with high-pressure safety switches. In accordance with the applicable code the high-pressureswitches with manual reset, called PZH (former DBK), may be backed up by high-pressure switches that requireresetting with a tool. The high-pressure switches that require resetting with a tool are called PZHH (former SDBK). If aPZHH cuts out, the corresponding PZH in the same compressor is faulty and must be replaced. The PZHH must be resetwith a blunt tool with a diameter of less than 6 mm. Insert this tool into the opening on the pressure switch and push thereset button in this location. These pressure switches are located at the discharge of each compressor.8.4 - Air side exchangerThe 30XQ coils are with internally grooved copper tubes with aluminum fins are available8.5 - FanThe fan is axial Flying Bird fans equipped with rotating shroud and made of composite recyclable material. Each motoris fixed with transverse supports. The motors are three-phase, with permanently lubricated bearings and insulation classF.8.6 - Electronic expansion valve (EXV)The EXV is equipped with a stepper motor (2785 to 3690 steps, depending on the model) that is controlled via the EXVboard. The EXV is also equipped with a sight glass that permits verification of the mechanism movement and hepresence of the liquid gasket.8.7 - Moisture indicatorLocated on the EXV, permits control of the unit charge and indicates moisture in the circuit. The presence of bubbles inthe sight-glass indicates an insufficient charge or non-condensable in the system. The presence of moisture changes thecolor of the indicator paper in the sight-glass.8.8 - Filter drierThe role of the filter drier is to keep the circuit clean and moisture-free. The moisture indicator shows, when it isnecessary to change the element. A difference in temperature between the filter inlet and outlet shows that the element isdirty. The filter should be replaced at least once per year.8.9 - SensorsThe units use thermistors to measure the temperature, and pressure transducers to control and regulate system operation(see 30XQ - Pro-Dialog Control IOM for a more detailed explanation).8.10 - 4-way valve4-way valve is used to realize change over automatically between cooling mode and heating mode. In fact, 4-way valvemostly acted during changeover of heating mode and defrost mode. The minimum pressure differential is 350kPa todrive valve changeover.NOTE: To decrease valve failure risk, when valve changeover is necessary at first running test or weather seasonsinterchange, it is not allowed to changeover operation mode until the maintenance and service persons ensure thevalve should keep present mode operating at least 10 minutes.Unit change operation mode from cooling mode to heating mode, first need operate 10 minutes at cooling mode, thenstop unit, select heating mode and start again. The process is same as the changeover from heating mode to coolingmode.Warning: to ensure valve reliable work, it will be better keep power on when unit is stopped, especially operates atcooling mode and defrost mode. If it has to cut off power to examine and repair, please check and verify the