Which is more Energy-Saving when the Air Source Heat Pump is Turned on at 35 Degrees or 45 Degrees
What is the most energy-saving setting for the air source heat pump? First of all, it should be made clear that the heat pump has heating, cooling and hot water units. When heating, we set the temperature of the air source heat pump controller for different heating terminals. If the heat pump is equipped with floor heating, it can be set at 35°C; if the heat pump is equipped with a fan, it can be set at 40°C; if the heat pump is equipped with a radiator, it can be set at 45°C.
For heat pump water heaters, which is more energy-saving when it is turned on at 35 degrees or 45 degrees? The set temperature of the air source heat pump water heater is closely related to the power consumption, but "power saving" needs to comprehensively consider factors such as operating efficiency, usage requirements and ambient temperature. The following is a specific analysis:
Principle and core conclusion
1. The lower the set temperature, the more power saving in theory
The energy efficiency ratio (COP) of the air source heat pump decreases as the target temperature increases. For example:
When heated to 35℃, the COP may be 4.0 (i.e. 1 kWh of electricity generates 4 times the heat);
When heated to 45℃, the COP may drop to 3.2 (the greater the temperature difference, the lower the efficiency).
Conclusion: Heating to 35℃ consumes less power.
2. Actual use needs to be combined with demand
If the temperature is set to 35℃ but cold water needs to be mixed frequently (such as taking a bath at 40℃ or above), it may be necessary to heat it multiple times or start electric auxiliary heating, which will consume more power.
If 45℃ is set directly, heating is in place at one time, reducing the need for secondary heating, which may be more energy-saving.
Key influencing factors
1. Ambient temperature
In summer, the ambient temperature is high, and the COP decreases slightly when heated to 45℃, narrowing the gap in power consumption with 35℃;
In winter, the ambient temperature is low, and the COP decreases significantly when heated to 45℃, and the power consumption increases significantly.
2. Water tank insulation performance
For water tanks with poor insulation, high temperature settings (such as 45℃) will cause more heat loss and require frequent heating, which may offset the high COP advantage.
3. Water use habits
For concentrated water use (such as once in the morning and once in the evening), it is recommended to set a high temperature to reduce the number of heating times;
For dispersed water use, a lower temperature can be set to utilize the high efficiency range of intermittent operation of the heat pump.
Data comparison example
Assuming that 200L of water is heated and the ambient temperature is 20℃:
35℃
45℃
Mixed mode
COP: 4.2
Power consumption (kWh): 2.4
Remarks: Direct use, no need to mix water
COP: 3.5
Power consumption (kWh): 3
Remarks: Need to heat to a higher temperature, COP decreases
COP: -
Power consumption (kWh): 3.2
Remarks: After heating at 35℃, mixed electric auxiliary heating to 45℃ consumes more power
Power saving suggestions
1. Prioritize usage needs: avoid setting too low a temperature for power saving, which will cause frequent heating or mixed water power consumption.
2. Seasonal adjustment: 40-45℃ can be set in summer, and 45-50℃ is recommended in winter (antifreeze is required in cold areas).
3. Enable the timing function: heat during low electricity consumption hours to reduce electricity costs.
4. Strengthen insulation measures: wrap the water tank pipes to reduce heat loss.
Summary
Pure theory: 35℃ saves about 20%-30% more electricity than 45℃;
Actual use: The temperature should be selected according to the water usage scenario to avoid inefficient secondary heating.
Optimal strategy: Set the temperature between 40-45℃ to balance energy efficiency and practicality.
