[0032] The defrosting method of the heat pump type air conditioner of the present invention will be described in further detail below in conjunction with the drawings and specific embodiments.
[0033] Such as figure 1 , figure 2 , image 3 Shown.
[0034] Set the outdoor heat exchanger coil temperature T z And outdoor ambient temperature T h And actual heating time H y And set the heating time h y It is connected to determine whether to enter the defrost operation mode. According to the outdoor ambient temperature T h 、The temperature Tz of the central coil of the outdoor heat exchanger, the actual heating time H y , Defrost time Hc to defrost.
[0035] Set the following parameters:
[0036] 1. Temperature setting: environmental temperature judgment t 1 , T 2 And three constants a, b, c, defrost end temperature G:
[0037] Preferred: t 1 The range is 8℃~14℃; t 2 The range of is -2°C to 2°C; the range of a is 0 to 0.4; the range of b is 0.6 to 1; the range of c is -10°C to -6°C; the range of G is 14°C to 18°C.
[0038] Best: t 1 12℃; t 2 Is 0°C; a is 0.2; b is 0.8; c is -8°C; G is 16°C;
[0039] 2. Time setting: initial setting heating time h y ’, the maximum heating time h max 、Minimum heating time h min , Set two defrost time h 1 , H 2 , The maximum defrost time h, constant d.
[0040] Preferred: Initially set heating time h y The range of ’is 35~45min; h max The range is 80~140min; h min The range is 25~35min; h 1 The range is 3~4min; h 2 The range of is 4~6min; the range of h is 7~9min; the range of d is 4~6min; the range of L is 0.5~2min; the range of M is 4~6min; the range of K is 6~10min; the range of N It is 10~30s; the range of R is 15~50s.
[0041] Best: Initially set heating time h y ’Is 40min; h max 120min; h min 30min; h 1 3min; h 2 Is 5min; h is 8min; d is 5min; L is 1min; M is 5min; K is 8min; N is 20s; R is 30s.
[0042] See figure 1.
[0043] When T ht 1 When, the unit does not enter the defrost operation mode.
[0044] In the following two situations, the unit enters the defrost operation mode:
[0045] ①, when t 1 ≥T h ≥t 2 If the temperature of the central coil of the outdoor heat exchanger is T z Meet T for continuous M minutes z h +c and H yh y , The unit enters defrosting;
[0046] ②, when T h 2 If the temperature of the central coil of the outdoor heat exchanger is T z Continuous M minutes meet: T z h +c and H yh y , The unit enters defrosting.
[0047] When the unit enters the defrost operation mode, the outdoor compressor stops. After N seconds, the outdoor fan stops, the four-way valve changes direction, and the compressor starts. The auxiliary electric heating of the indoor unit is turned on, and the fan automatically switches to a low wind gear, and runs for L minutes and stop for L minutes.
[0048] Unit defrost end judgment: the temperature of the central coil of the outdoor heat exchanger T zG℃, or defrosting time Hc>K minutes, the defrosting ends.
[0049] At the end of the defrosting of the unit, the indoor auxiliary electric heater is turned off, the indoor fan is turned off, and the outdoor compressor is stopped. After N seconds, the four-way valve changes direction, the fan starts, and the compressor starts.
[0050] See figure 2.
[0051] According to the actual defrost time Hc is greater than the set defrost time h 1 , Or the actual defrost time Hc is less than or equal to the set defrost time h 1 And greater than or equal to the set defrost time h 2 , Or the actual defrost time Hc is greater than the set defrost time h 2 Three different situations, adopt different methods to reconfirm the next heating time h y :
[0052] When Hc>h 1 And h y ≥h min +d, then set the heating time h this time y The heating time h should be set last time y Subtract d; when Hc>h 1 And the heating time h was set last time y min +d, set the heating time h this time y constant;
[0053] When h 1 ≥Hc≥h 2 , Then set the heating time h this time y constant;
[0054] When Hc 2 And h y ≤h max -d, then set the heating time h this time y The heating time h should be set last time y Add d on the basis of;
[0055] When Hc 2 And h yh max -d, set the heating time h this time y constant.
[0056] See image 3.
[0057] When the unit is in heating operation, the outdoor temperature sensor always detects the temperature T of the central coil of the outdoor heat exchanger z And outdoor ambient temperature T h If T ht 1 , Then the unit does not enter the defrost procedure. If t 1 ≥T h ≥t 2 , Then determine T z Whether T has been met for M consecutive minutes z h +c, if it is not satisfied, it will not enter the defrost; when T z Meet T for continuous M minutes z h +c, then determine the actual heating time H y Is it greater than the set heating time h y : If H y ≤h y , Then the unit does not enter defrosting until H yh y , The unit defrosts. If T h 2 , Then determine T z Whether T has been met for M consecutive minutes z h +c, if it is not satisfied, it will not enter the defrost; when T z Meet T for continuous M minutes z h +c, then determine the actual heating time H y Is it greater than the set heating time h y If H y ≤h y , Then the unit does not enter defrosting until H yh y , The unit defrosts. When the unit is defrosting, the outdoor compressor stops. After N seconds, the outdoor fan stops, the four-way valve changes direction, and the compressor starts. The auxiliary electric heating of the indoor unit is turned on, and the fan automatically switches to a low wind gear, and it runs for L minutes and stop for L minutes. Defrost end judgment: the temperature of the central coil of the outdoor heat exchanger T zG℃ or defrosting time Hc>K minutes, the defrosting is over. At the end of defrosting, the indoor auxiliary electric heater is turned off, the indoor fan is turned off, and the outdoor compressor is stopped. After N seconds, the four-way valve changes direction, the fan starts and the compressor starts. After defrosting, adjust the next heating time h according to the actual defrosting time Hc. y. The specific method is as follows: when Hc>h 1 And the heating time h was set last time y ≥h min +d, then set the heating time h this time y The heating time h should be set last time y Subtract d; when Hc>h 1 And set the last heating time h y min +d, set the heating time h this time y Remain unchanged; when h 1 ≥Hc≥h 2 , Then set the heating time h this time y Keep unchanged; when Hc 2 And the heating time h was set last time y ≤h max -d, then set the heating time h this time y Increase d; when Hc 2 And the heating time h was set last time yh max -d, set the heating time h this time y Keep the last set time unchanged.
[0058] Taking the above-mentioned optimal parameters as an example, a complete defrosting process is given below:
[0059] Set heating time h in the first defrost cycle y =h y ’. When the unit is in hot operating state, the temperature sensor located in the middle of the outdoor heat exchanger coil and the outdoor temperature sensor always detect the temperature T of the middle coil of the outdoor heat exchanger. z And outdoor ambient temperature T h If T h12℃, then the controller does not enter the defrost program. If 12℃≥T h ≥0℃, then judge T z Whether T has been satisfied for 5 consecutive minutes z <0.2T h -8℃, if it is not satisfied, it will not enter into defrosting; when T z Meet T for 5 minutes z <0.2T h -8℃, then determine the actual heating time H y Is it greater than the set heating time h y That is 40min, if H y ≤40min, then the unit does not enter the defrost; until H y40min, the unit defrosts. If T h <0℃, then judge T z Whether T has been satisfied for 5 consecutive minutes z <0.8T h -8℃, if it is not satisfied, it will not enter into defrosting; when T z Meet T for 5 minutes z <0.8T h -8℃, then judge the heating time H y Is it greater than the set heating time h y If H y ≤40min, then the unit will not enter defrosting until H y40min, the unit defrosts. When the unit enters the defrosting operation mode, the outdoor compressor stops. After 20 seconds, the outdoor fan stops, the four-way valve changes direction, the compressor starts, the auxiliary electric heating of the indoor unit is turned on, and the fan automatically switches to a low wind gear and keeps on for 1 minute. Stop for 1 minute to run. Defrost end judgment: the temperature of the central coil of the outdoor heat exchanger T z16℃ or defrost time Hc>8 minutes. At the end of defrosting, the indoor auxiliary electric heater is turned off, the indoor fan is turned off, and the outdoor compressor is stopped. After 30 seconds, the four-way valve changes direction, the fan starts, and the compressor starts. After the defrosting is over, adjust the next heating time h according to the defrosting time Hc (the length of this time) y , The specific method is as follows: when Hc>5min and 40min≥30+5(h y ≥h min +d), then the actual heating time h this time y Minus d is h y =40min-5min=35min; when 5min≥Hc≥3min, then set heating time h next time y Keep the actual heating time h y =40min unchanged; when Hc<3min and 40min≤120min-5(h y ≤h max -d), then set the heating time h this time y Increase d or h y =40+5=45.
