Abstract: In this paper, some shortcomings of water source heat pump units are described in terms of their potential safety hazards, usage, water conditions, winter heating, maintenance and environmental pollution.
Keywords: heat pump safety water unit paralysis First, the unit's own security risks
1. This unit must be equipped with a dedicated power supply that requires tight control of voltage fluctuations (-10% to + 10%).
2. Due to technical immaturity, the unit is likely to continue its work (as usual) under hazardous conditions even in the event of a short circuit.
3. Therefore, the unit must be equipped with a dedicated automatic air switch, absolutely prohibit the use of knife switch, and the current control is also very strict (ratio of 1.5 times) and to configure phase protection.
Second, inconvenient to use more reliable
1. As long as it is restarted after shutdown, power-on warm-up time is very long, it must be 12 hours later.
2. If the unit stops the heating operation in winter, the controller must keep communication with the unit and must not be cut off, otherwise the pipes will be cracked, the unit is in a state of paralysis, the more serious is the whole machine is frozen, the difficulty of maintenance can be Think of it (because the power is beyond the control of human beings, there may even be a power failure inadvertently operating mistakes).
Third, the instability of water
1. Need to measure the adequacy of water in advance and reliable testing of water quality, credibility.
2. It is absolutely forbidden to have the same source of use upstream of the water source or the unit will not function properly.
Fourth, the winter heating effect is not ideal
1. Than the normal air-conditioning heating temperature is low 5-6 ℃.
2. Need to configure auxiliary heating equipment.
Fifth, the use of the host switch is more stringent requirements: frequent operation will lead to paralysis unit (not more than four times per hour).
Six, the water system to be equipped with expansion tank, the circulating water must be clean, or quickly scaling effect of use and operation must be to maintain adequate water flow, otherwise it will cause the water heater cracking, more often to clean the water Filter, inconvenience to use. Water source heat pump in use to be shut down for maintenance.
Seven, the unit in the overall system maintenance more complicated and difficult.
Eight, serious groundwater pollution.