Refrigerant Lines; System Evacuation And Charging - Carrier 40MKCC Service Manual

REFRIGERANT LINES

General refrigerant line sizing:
1 The outdoor units are shipped with a full charge of R410A
refrigerant. All charges, line sizing, and capacities are based
on runs of 25 ft. (7.6 m). For runs over 25 ft. (7.6 m), refer
to the Residential Long Line Guide.
2 Minimum refrigerant line length between the indoor and
outdoor units is 10 ft. (3 m).
3 Refrigerant lines should not be buried in the ground. If it is
necessary to bury the lines, not more than 36- -in (914 mm)
should be buried. Provide a minimum 6- -in (152 mm) vertical
rise to the service valves to prevent refrigerant migration.
4 Both lines must be insulated. Use a minimum of 1/2- -in.
(12.7 mm) thick insulation. Closed- -cell insulation is
recommended in all long- -line applications.
5 Special consideration
interconnecting tubing from the building structure. Isolate the
tubing so that vibration or noise does not transmit into the
structure.
IMPORTANT: Both refrigerant lines must be insulated
separately.
S The following maximum lengths are allowed:
Table 13 – Maximum Refrigerant Line Lengths
Max Line
Unit Size
Length* ft(m
18K-34K 250 (76.2)
Note: For lengths greater than 25 ft. (7.6 m), refer to the Residential
Long Line Guide.
*Maximum actual length not to exceed 200 ft. (61 m). Total equivalent
length accounts for losses due to elbows or fitting. See the Long Line
Guideline for details.
S The following are the piping sizes.
Table 14 – Pipe Sizes
Indoor Unit Tube
Indoor Unit Outdoor Unit Sizes (in)
Liquid
24AHA418
40MKCB18C- - - - 3
124ANS018
24AHA424
40MKCB34C- - - - 3
124ANS024
24AHA430
40MKCB34C- - - - 3
124ANS030
24AHA436
40MKCB34C- - - - 3 3/8
124ANS036
25HHA424
40MKQB34C- - - - 3
224ANS024
25HHA430
40MKQB34C- - - - 3
224ANS030
25HHA436
40MKQB34C- - - - 3
224ANS036
Note: Both lines need to be insulated using at least 1/2 inch closed
foam insulation.
Refrigerant Charge
Table 15 – Charge Requirements
Nominal
System
Capacity
Outdoor Unit
Type
kBTU/Hr
018 24AHA418A003 124ANS018000
024 24AHA424A003 124ANS024000
Cooling
Only
030 24AHA430A003 124ANS030000
034 24AHA436A003/5/6 124ANS036000
024 25HHA424A003 224ANS024000
Heat
030 25HHA430A003 224ANS030000
Pump
034 25HHA436A003/5/6 224ANS036000
The above additional charge is required amount for line lengths up to
25 ft (7.6 m). For line lengths exceeding 25 ft. (7.6 m), additional
charge will be required. Refer to the Residential Long Line Guide.
should be given to isolating
Max Elevation Max
(ID over OD) Elevation (OD
ft ( m) over ID) ft (m)
65 (19.8) 200 (61)
TXV Kit Tube Outdoor Unit
Sizes (in) Tube Size (in)
Vapor Liquid Vapor Liquid Vapor
5/8 5/8 5/8
3/4 3/4 3/4
3/4 3/4 3/4
3/4 3/8 3/4 3/8 7/8
3/4 3/4 3/4
3/4 3/4 3/4
3/4 3/4 7/8
Charge to
Sub- - cooling
Indoor Unit Delta from
Rating Plate
Value
40MKCB18C- - - - 3 12
40MKCB34C- - - - 3 12
40MKCB34C- - - - 3 12
40MKCB34C- - - - 3 8
40MKCB34C- - - - 3 14
40MKCB34C- - - - 3 11
40MKCB34C- - - - 3 14
Metering Device
The 40MKC(Q)*C unit uses a TXV while the outdoor unit uses a
type B accurator. The cooling metering device is installed with the
indoor unit. The heating metering device is installed with the
outdoor unit. One metering device is required for the cooling only
system and two are required for the heat pump systems. Refer to
Table 16 for a breakdown of each unit's metering devices.
Table 16 – Metering Devices
Cooling Only
System Size
kBTU/hr
40MKCB**C
018 TXV
024 TXV
030 TXV
034 TXV
SYSTEM EVACUATION AND
CHARGING
CAUTION
!
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment
damage or improper operation.
Never use the system compressor as a vacuum pump.
Refrigerant tubes and indoor coil should be evacuated using the
recommended deep vacuum method of 500 microns. The alternate
triple evacuation method may be used if the procedure outlined
below is followed. Always break a vacuum with dry nitrogen.
SYSTEM VACUUM AND CHARGE
Using Vacuum Pump
1 Completely tighten flare nuts A, B, C, D, connect manifold
gage charge hose to a charge port of the low side service
valve (see Fig. 17).
2 Connect charge hose to vacuum pump.
3 Fully open the low side of manifold gage (see Fig. 18).
4 Start the vacuum pump.
5 Evacuate using either deep vacuum or triple evacuation
method.
6 After evacuation is complete, fully close the low side of the
manifold gage and stop the vacuum pump operation.
7 The factory charge contained in the outdoor unit is good for up
to 25 ft. (8 m) of line length. For refrigerant lines longer than
25 ft. (8 m), add charge, up to the maximum allowable length,
as specified in the residential Long Line Application Guide.
8 Disconnect charge hose from charge connection of the low
side service valve.
9 Fully open service valves B and A.
10 Securely tighten caps of service valves.
Refrigerant
Outdoor Unit
A
B
Service Valve
Fig. 17 – Service Valve
17
Heat Pumps
40MKQB**C 25HHA4/224ANS
- -
TXV 0.049"
TXV 0.055"
TXV 0.063"
Indoor Unit
Low Side C
D
High Side
A07360