Systems and methods for charging refrigerant into a climate control system
Methods and related systems for charging a refrigerant into a climate control system. In an embodiment, the method includes (a) coupling a storage tank to a refrigerant loop of the climate control system through a charging valve; (b) opening and closing the charging valve in a plurality of cycles; and (c) flowing refrigerant from the storage tank to the refrigerant loop through the charging valve when the charging valve is open, during (b). In addition, the method includes (d) determining a detected saturated temperature of the refrigerant within the refrigerant loop after each cycle of the plurality of cycles; and (e) adjusting an amount of time that the charging valve is open during each cycle of the plurality of cycles during (b) as a function of the detected saturated temperature from a previous cycle of the plurality of cycles.
1. A climate control system comprising:
a refrigerant loop for circulating refrigerant within the climate control system;
a connection associated with the refrigerant loop, the connection configured to couple to a charging valve to supply refrigerant into the refrigerant loop; and
a controller configured to:
cause the charging valve to open and close in a plurality of cycles when the charging valve is coupled to the connection;
determine a detected saturated temperature of the refrigerant within the refrigerant loop after each cycle of the plurality of cycles; and
adjust an amount of time that the charging valve is open during each cycle of the plurality of cycles as a function of the detected saturated temperature from a previous cycle of the plurality of cycles.
2. The climate control system of claim 1 , wherein the connection includes a releasable connection.
3. The climate control system of claim 1 , wherein the controller configured to adjust the amount of time that the charging valve is open during each cycle is further configured to adjust the amount of time as a function of a difference between a target saturated temperature and the detected saturated temperature from the previous cycle of the plurality of cycles.
4. The climate control system of claim 1 , further comprising a pressure sensor coupled to the refrigerant loop at a discharge side of a heat exchanger of an outdoor unit, and
wherein the controller configured to determine the detected saturated temperature is further configured to determine the detected saturated temperature based on the pressure.
5. The climate control system of claim 1 , wherein the controller configured to determine the detected saturated temperature is further configured to determine a target saturated temperature based on a predetermined relationship between the detected saturated temperature and a liquid temperature of the refrigerant loop, wherein the liquid temperature of the refrigerant loop is determined at a discharge side of a heat exchanger of an outdoor unit of the climate control system.
6. The climate control system of claim 5 , wherein the predetermined relationship is derived based on a full charge of refrigerant within the refrigerant loop.
7. The climate control system of claim 1 , wherein the controller configured to adjust the amount of time that the charging valve is open during each cycle is further configured to adjust the amount of time that the charging valve is open during each cycle as a function of difference between a target saturated temperature and the detected saturated temperature, and a time derivative of the difference.
8. The climate control system of claim 1 , wherein the controller configured to adjust the amount of time that the charging valve is open during each cycle is further configured to adjust the amount of time that the charging valve is open by adjusting a duty cycle of the charging valve during each cycle according to the following expression:
Duty
Cycle
=
(
D
C
n
o
m
)
(
K
P
)
(
Δ
T
SAT
)
+
(
K
D
)
(
d
(
Δ
T
S
A
T
)
d
t
)
,
wherein DC nom comprises a nominal duty cycle value, ΔT SAT comprises a difference between a target saturated temperature and the detected saturated temperature,
d
(
Δ
T
S
A
T
)
d
t
comprises a time derivative of ΔT SAT , and K P and K D comprise constant values.
9. The climate control system of claim 8 , wherein the controller configured to adjust the amount of time that the charging valve is open during each cycle is further configured to limit the duty cycle of the charging valve during each cycle to a predetermined amount of time that is less than a total time of each cycle.
10. The climate control system of claim 1 , wherein each of the plurality of cycles has a fixed duration.
11. The climate control system of claim 1 , wherein the controller configured to determine the detected saturated temperature is further configured to determine a target saturated temperature based on at least one of:
a length of a fluid flow line of the climate control system; or
a difference in elevation between an outdoor unit and an indoor unit of the climate control system.
12. A controller for directing a charging of refrigerant into a refrigerant loop of a climate control system, the controller comprising:
a memory configured to store computer-readable program code including a refrigerant charging-related software application; and
a processor configured to access the memory, and execute the computer-readable program code including the refrigerant charging-related software application to cause the processor to at least:
control a charging valve coupled to the refrigerant loop to open and close in a plurality of cycles, the charging valve configured to supply refrigerant to the refrigerant loop of the climate control system;
receive a detected saturated temperature of the refrigerant within the refrigerant loop after each cycle of the plurality of cycles; and
adjust an amount of time that the charging valve is open during each cycle of the plurality of cycles as a function of the detected saturated temperature from a previous cycle of the plurality of cycles.
13. The controller of claim 12 , wherein the processor configured to access the memory, and execute the computer-readable program code including the refrigerant charging-related software application to cause the processor to adjust the amount of time that the charging valve is open during each cycle further causes the processor to adjust the amount of time as a function of a difference between a target saturated temperature and the detected saturated temperature from the previous cycle of the plurality of cycles.
14. The controller of claim 12 , wherein the processor configured to access the memory, and execute the computer-readable program code including the refrigerant charging-related software application to cause the processor to adjust the amount of time that the charging valve is open during each cycle further causes the processor to adjust the amount of time as a function of a difference between a target saturated temperature and the detected saturated temperature, and a time derivative of the difference.
15. The controller of claim 14 , wherein the processor configured to access the memory, and execute the computer-readable program code including the refrigerant charging-related software application to cause the processor to adjust the amount of time that the charging valve is open during each cycle further causes the processor to limit a duty cycle of the charging valve during each cycle to a predetermined amount of time that is less than a total time of each cycle.
16. The controller of claim 12 , wherein the processor configured to access the memory, and execute the computer-readable program code including the refrigerant charging-related software application to cause the processor to adjust the amount of time that the charging valve is open during each cycle further causes the processor to adjust the amount of time that the charging valve is open during each cycle is further configured to adjust the amount of time that the charging valve is open by adjusting a duty cycle of the charging valve during each cycle according to the following expression:
Duty
Cycle
=
(
D
C
n
o
m
)
(
K
P
)
(
Δ
T
SAT
)
+
(
K
D
)
(
d
(
Δ
T
S
A
T
)
d
t
)
,
wherein DC nom comprises a nominal duty cycle value, ΔT SAT comprises a difference between a target saturated temperature and the detected saturated temperature,
d
(
Δ
T
S
A
T
)
d
t
comprises a time derivative of ΔT SAT , and K P and K D comprise constant values.
17. The controller of claim 12 , wherein each of the plurality of cycles has a fixed duration.
18. A non-transitory machine-readable medium including instructions that, when executed by a processor, cause the processor to:
(a) open and close a charging valve coupled between a storage tank and a refrigerant loop of a climate control system in a plurality of cycles, wherein refrigerant is configured to flow from the storage tank to the refrigerant loop through the charging valve when the charging valve is open;
(b) receive a detected saturated temperature of the refrigerant within the refrigerant loop after each cycle of the plurality of cycles; and
(c) adjust an amount of time that the charging valve is open during each cycle of the plurality of cycles during (a) as a function of the detected saturated temperature from a previous cycle of the plurality of cycles.
19. The non-transitory machine-readable medium of claim 18 , wherein the instructions, when executed by the processor, further cause the processor to adjust the amount of time that the charging valve is open during each cycle during (a) as a function of a difference between a target saturated temperature and the detected saturated temperature.
20. The non-transitory machine-readable medium of claim 18 ,
wherein the instructions, when executed by the processor, further cause the processor to adjust a duty cycle of the charging valve during each cycle of the plurality of cycles to adjust the amount of time that the charging valve is open during each cycle, and
wherein the instructions, when executed by the processor, further cause the processor to adjust the duty cycle of the charging valve according to the following expression:
Duty
Cycle
=
(
D
C
n
o
m
)
(
K
P
)
(
Δ
T
SAT
)
+
(
K
D
)
(
d
(
Δ
T
S
A
T
)
d
t
)
,
wherein DC nom comprises a nominal duty cycle value, ΔT SAT comprises a difference between a target saturated temperature and the detected saturated temperature,
d
(
Δ
T
S
A
T
)
d
t
comprises a time derivative of ΔT SAT , and K P and K D comprise constant values.