Low temperature heat pump units, including air-water type low ambient temperature air source heat pump (chiller) units, low ambient temperature air source heat pump water heaters, low temperature type commercial or industrial heat pump water heaters and heat pump water heaters for similar purposes, have their heating performance coefficient tested in accordance with GB/T25127.1-2010 and GB/T25127.2-2010. See the following table for different outlet water temperatures, nominal load and partial load test conditions at the use side
Heating part load test condition
|project||load/%||Use side||Heat source side|
|Water volume M³/（h·KW）||Outlet water temperature||Dry bulb temperature||Wet bulb temperature|
|heating||100||0.172||Select the setting according to its rated outlet temperature（35℃、41℃、55℃）||-12||-14|
According to the rated outlet water temperature of the low-temperature heat pump unit, the actual heating capacity and the heating performance coefficient of the nominal working condition COPh are measured under the specified value of full load and rated working condition.
According to the rated outlet water temperature of the low-temperature heat pump unit, the heat capacity and heat performance coefficient COP (h, - 20 ℃) are measured at the specified value under full load and low temperature conditions (dry bulb temperature at the outdoor side - 20 ℃).
The comprehensive partial load performance coefficient of heating is calculated according to formula (1) of GB/T25127.1-2010, and the IPLV (H) value is calculated based on the IPLV coefficient of Beijing.
Electric auxiliary heating control on detection method
For the unit with built-in electric auxiliary heating system, set the auxiliary electric heating to the ON state, set the outlet water temperature to the rated outlet water temperature of the unit (if there are multiple outlet water temperatures, the outlet water temperature at the top), the laboratory water supply temperature to "set the outlet water temperature to - 10 ℃" (or inject cold water with the initial water temperature of 9 ℃ into the test tank), and the outdoor dry bulb temperature to - 18 ℃ → - 19 ℃ → - 15 ℃ respectively, After each adjustment to a stable temperature point, run for at least 10 minutes or the time provided by the manufacturer. During this time, record the passing current of the auxiliary electric heating system, and observe whether the auxiliary electric heating system is started.