Hot water tank overflowing

What is the reason for the overflow of the water tank of the air source heat pump hot water cylinders?

1. If the water tank overflows, the water tank cannot automatically enter water, and must be filled manually; the water tank cannot enter water. High water level switch failure:
1) It is faulty, the high water level switch is broken; or the scaling fails, replace with a new high water level switch.
2) Impurities are adsorbed on the floating ball, making the floating ball unable to move. Take out the switch to remove dirt and impurities.
3) If the high water level switch is installed higher than the overflow port, the switch will not work. Reinstall the high water level switch.

2. The water tank cannot automatically enter water/the water tank cannot enter water:
1) The low water level switch is faulty; replace the low water level switch.
2) The solenoid valve is faulty; replace the solenoid valve.
3) The temperature sensor is faulty; the temperature sensor is replaced or the order of the high, medium and low water level probes is wrong.

The solution to the overflow of the water tank of the air source heat pump hot water cylinders:

1. Check the cause of the overflow to see if the water replenishment solenoid valve is stuck with dirt, the cold water is out of control, and has been flowing into the small water tank, or it is caused by the failure of the water level control. The cold water replenishment system cannot normally sense the water level signal to the cold water replenishment processing system.

2. Observation of power failure: If the water tank is still overflowing when the power is off, that is, when the solenoid valve is not energized, the water supply solenoid valve is stuck with sand or debris. Otherwise, the water level control system has failed.

3. Water overflow solution: the water level is out of control mainly because the probe or the water level switch has too much scale. It can be solved by sanding and cleaning with sandpaper. The other is the loss of water level control signal. Check whether the wire is broken, such as a mouse bite or other circumstances, or the wire is broken or the previous wiring is not in good contact. Reconnect and wrap the bakelite. It may also be that the AC contactor or intermediate relay contact has failed. Replacement can resolve the fault.