Johnson Controls YVAHP036B21S, Инструкция по эксплуатации

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OUTDOOR UNITS
TC-16001-rev.5
2-23
< Condition for Starting Defrost Operation >
(1) Standard Defrost
(a) Temperature Condition
Temperature
Conditions
under
Defrost
Operation
Defrost Operation
Stop Area
Defrost Operation
Start Area
Outdoor Temperature [°F (°C)]
28
(-2)
41
(5)
14
(-10)
-6
(-21)
5
(-15)
23
(-5)
42
(6)
50
(10)
59
(15)
Outdoor Evaporating
Te
mperature (T
e) [°F (°C)
]
(b) Condition of Operating Time for Defrost Operation Start
The defrost operation starts when the temperature condition shown in “(a) Temperature Condition”
is met after a heating operation of 40 to 120 minutes. The heating operation time is determined by
estimating the amount of frost on the heat exchanger.
(2) Forced Defrost
The “Forced Defrost” starts when all the following conditions are met.
(a) The reversing valve is “ON” for more than 120 minutes.
(b) The outdoor temperature is 50
o
F (10
o
C) or lower.
(c) The accumulated heating operation time is more than 60 minutes.
(The accumulated time is reset when the operation is stopped or the defrost operation is performed.)
(d) The compressor is operated continuously for more than 90 seconds.
(e) The outdoor evaporating temperature is lower than 41
o
F (5
o
C) right before the operation starts.
(f) The pressure switch for control is “OFF”.
< Condition for Completing Defrost Operation >
The defrost operation stops when any of the following conditions is met.
(1) The outdoor evaporating temperature reaches 77
o
F (25
o
C) within 2 minutes after the defrost operation
starts.
(2) The outdoor evaporating temperature reaches 59
o
F (15
o
C) (the outdoor temperature < 50
o
F (10
o
C))
and high pressure reaches 218psi (1.5MPa) after a lapse of 2 minutes or more from the defrost
operation start.
(3) The outdoor evaporating temperature reaches 41
o
F (5
o
C) (the outdoor temperature > 50
o
F (10
o
C))
after a lapse of 2 minutes or more from the defrost operation start.
(4) The temperature at the top of the compressor reaches 270
o
F (132
o
C).
(5) The pressure switch for control is “ON”.
(6) The high pressure reaches 479psi (3.3MPa) within 20 seconds after the defrost operation starts.
(7) The high pressure reaches 450psi (3.1MPa) after a lapse of 2 minutes or more from the defrost
operation start.
(8) More than 9 minutes have passed from the defrost operation start.
NOTE:
The defrost operation does not start immediately even if the above conditions are met, because these
conditions may be met temporarily depending on the refrigerant system variability.
The defrost operations start when these conditions are met continuously for a certain period of time.