Troubleshooting of Air Source Heat Pump Unit

Troubleshooting of Air Source Heat Pump Unit

When an air source heat pump unit fails, do you panic and don't know where to start troubleshooting. Don't worry, today the okmarts.com editor will teach you how to troubleshoot, including: troubleshooting steps, common failures and troubleshooting methods of the unit, and typical failure engineering cases for everyone to learn and refer to.

　　 One, understand and troubleshoot

　　 1. Through telephone communication or on-site inspection to understand the unit's operating status, fault conditions, and fault codes;

　　 2. Preliminarily judge the cause of the fault by querying the fault code;

　　 3. Combine fault codes and maintenance experience to find faults and replace faulty parts;

　　 4. Debug and run the unit.

　　 2. Common troubleshooting of the unit

　　Fault state: the unit is not running

　　 Possible causes of failure: power failure; loose wiring of the unit power supply; blown out of the unit control power fuse

　　 Treatment measures: disconnect the power switch, check the power supply; find out the cause and repair; replace the new fuse

　　Fault state: the pump is running but the water does not circulate or the pump is noisy

　　 Possible causes of failure: water shortage in the water system; air in the water system; all valves of the water system are open; the water filter is dirty and blocked

　　 Treatment measures: check the system water replenishment device, and replenish water to the system; remove the air in the water system; fully open the water system valve; clean the water filter

　　Fault state: the heating capacity of the unit is low

　　 Possible causes of failure: insufficient refrigerant; poor heat preservation of the water system; clogged filter dryer; poor heat dissipation of the air heat exchanger; insufficient water flow

　　 Treatment measures: leak detection of the system and charge refrigerant; strengthen the heat preservation of the water system; replace the dry filter; clean the air heat exchanger; clean the water filter

　　Fault state: the compressor does not run

　　Possible causes of failure: power failure; loose wiring; compressor overheating protection; excessive water temperature; insufficient water flow

　　 Treatment measures: find out the cause and solve the power failure; find out the loose point and repair it; find out the heat cause and remove the fault and then turn on the machine; reset the water temperature; clean the water filter to remove the air in the system

　　Fault state: the compressor is running noisy

　　 Possible cause of failure: Liquid preparation enters the compressor; internal parts of the compressor are damaged

　　 Treatment measures: check whether the expansion valve is invalid; replace the compressor

　　Fault state: the fan does not run

　　 Possible causes of failure: loosening of the fan fixing screws; burning of the fan motor; damage to the fan capacitor

　　 Treatment measures: tighten the set screws; replace the fan; replace the fan capacitor

　　Fault state: the compressor is running, but the unit is not heating

　　 Possible causes of failure: all refrigerant leaks; compressor failure

　　 Treatment measures: system leak detection and refrigerant charge; replacement of compressor

　　Fault state: the unit water flow is too low protection

　　 Possible cause of failure: insufficient water flow in the system; water flow switch not reset

　　 Treatment measures: clean the water filter to remove the air in the system; adjust or replace the water flow switch

　　 Failure status: Exhaust pressure is too high

　　 Possible causes of failure: too much refrigerant; non-condensable gas in the fluorine circuit system; insufficient water flow

　　 Treatment measures: discharge excess refrigerant; discharge non-condensable gas; check water system, increase water flow

　　Fault state: suction pressure is too low

　　Possible cause of failure: The filter drier is blocked; the pressure drop through the heat exchanger is too large

　　 Treatment measures: replace the dry filter; check whether the opening of the thermal expansion valve is appropriate

　　Fault state: the compressor loses oil

　　 Possible cause of failure: insufficient lubricant

　　 Treatment measures: add lubricant

　　 Three, engineering case

　　Project case one

　　Fault reflection: The unit is not heating.

　　Unit configuration: a household circulating 1.5P unit; the water tank is a 200L thermal insulation water tank.

　　 On-site situation: After the maintenance personnel arrived at the site, they found that the compressor of the main engine could not be turned on normally, so the main engine could not be used normally.

Fault analysis: check the host panel, the display is normal, the compressor is not working after the operation is turned on, check the line of the unit, the wiring is firm and reliable, after checking the line voltage, it is found that the main board has the output compressor voltage, and the capacitance capacity is measured, and it is found to be out of capacity. It is judged that the capacitor is damaged. After replacing the new capacitor, the unit works normally.

　　Solution: Replace with a new capacitor.

　　Project case two

　　Fault reflection: A user reports that the user’s unit has a fault and high temperature.

　　Unit configuration: The unit is a 1P static unit, and is equipped with a pressure water tank of 150L.

　　 On-site situation: After my maintenance staff came to repair, it was found that the unit had a high temperature when the hot water was heated to 50°, that is, the exhaust gas was too high and alarmed.

Fault analysis: According to the on-site situation, the unit has a high temperature alarm when the hot water is heated to 50°, which eliminates the high temperature alarm caused by dirty pipeline; the detection probe is connected normally, the temperature is displayed normally, and the probe problem is eliminated; check the water tank The temperature probe was found to be not placed to the end, so it is judged that the temperature sensor of the water tank was not placed in place, which caused the unit to detect the water temperature incorrectly (lower). When the water in the water tank was heated to the upper limit temperature, it continued to heat, which caused high temperature. Call the police.

　　Solution: After placing the temperature probe to the bottom and fixing it, the unit runs normally.

　　Project case three

　　Fault reflection: a high temperature fault occurs in the operation of the unit.

　　Unit configuration: a household static 1.5P unit; the water tank is a 200L insulated water tank.

　　 Scene situation: After the unit has been running for a period of time, the water temperature cannot rise, and a high temperature alarm appears after half an hour of operation.

　　Fault analysis: After running for a period of time, check that the evaporation temperature of the unit is always close to the ambient temperature, and the exhaust temperature rises slowly. It was detected that the current of the unit was too low, and there was no pressure in the unit system when connected to the pressure gauge, so it was judged that the unit had leaked fluorine. After inspection, it was found that there was oil stains at the connection between the copper pipe and the water tank. After reconnection, vacuumize and inject fluorine. The unit can operate normally.

　　Solution: Re-inject fluorine.

　　Project case four

　　Fault reflection: A trip occurred during the commissioning of the unit and the unit could not be started.

　　Unit configuration: The unit is 1.5HP.

　　 On-site situation: On-site commissioning personnel found that the compressor did not start after the unit was energized.

Fault analysis: check all power lines, no short circuit or wrong connection in the main circuit is found, check other lines are not loose; open the compressor junction box, check the wiring and find that the compressor terminal is off, after rearranging it, fix the terminal Operating normally. Due to the unfixed production process or the vibration during transportation, the compressor wiring terminals fall off, causing the compressor to be short-circuited when the compressor is powered on, so the phenomenon of tripping occurs.

　　Solution: Arrange the lines and fix the terminals.

　　Project case five

　　Fault reflection: unable to refill water normally.

　　Unit configuration: The unit is 1.5HP.

　　 On-site situation: On-site maintenance personnel found that the unit heating operation is normal, and the water level display is normal, but after the water level is lower than the set water level, the solenoid valve cannot be opened normally and water cannot be supplied.

　　Fault analysis: Pull the water level higher, check the solenoid valve wire stub in the unit, check that the power supply can be normal, and then check the solenoid valve coil resistance value, the resistance value is normal. Open the solenoid valve, and it is found that impurities enter the solenoid valve, causing the solenoid valve to jam and fail to open normally. After cleaning the solenoid valve, it can open and work normally.

　　Solution: Clean the solenoid valve.

　　Project case 6

　　Fault reflection: display 05E (high voltage fault).

　　Unit configuration: The unit is 1.5HP.

　　 On-site situation: On-site maintenance personnel found that the unit had been running for a period of time and showed 05E fault.

　　Fault analysis: The unit reports a fault after running for a period of time, which can basically be judged as a condensing side problem. Check that there is no shortage of water in the water tank, check the filter, and find a large amount of dirt in the filter. Therefore, the fault is caused by insufficient water flow due to blockage of the pipeline. After cleaning the filter, the unit can operate normally.

　　Solution: Clean the filter to ensure the circulating water flow.

　　Project case 7

　　Fault reflection: The unit is not heating.

　　 On-site situation: On-site maintenance personnel found that the panel temperature displayed 50 degrees, and the actual water temperature was obviously lower.

　　Fault analysis: The water in the water tank was discharged, and it was found to be obviously inconsistent with the temperature of the panel. The resistance value of the water tank probe was measured and the resistance value was found to be abnormal. After replacing the water tank probe, the water temperature displayed 25℃, and the unit worked normally.

　　Solution: Replace the water tank probe.

　　Project case eight

　　Fault reflection: The unit cannot heat.

　　 On-site situation: The panel displays 01E (phase error).

　　Fault analysis: 01E is a phase error fault, that is, the phase sequence of the 3 live wires supplied by the host is incorrect. After the phase sequence is adjusted, the unit works normally.

　　Solution: Adjust the phase sequence of the unit.