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NOTE: No AccuRater
t
is required on 38HDS sys-
tems. The 38HDS systems have a TXV (thermostatic
expansion valve) in the condensing unit for refriger-
ant metering and control.
e. On heat pump installations, install factory-supplied pis-
ton in the AccuRater metering device located in the
service valve on the outdoor unit (Fig. 10). Make sure
Teflon seal on the piston faces toward the outdoor unit.
Use Table 4 to verify the correct piston for your sys-
tem has been shipped with the unit. Refer to 38BK
installation instructions for more details.
f. Install a liquid line filter drier near the outdoor unit
(38HDC and 38BK). On heat pump systems, a bi-flow
filter drier must be used. DO NOT install a filter drier
in 38HDS systems.
3. Insulate and caulk wall openings to reduce air infiltration
and refrigerant pipe vibrations on structure.
4. Evacuate piping, if necessary. If either refrigerant piping
or the indoor coil is exposed to atmospheric conditions,
it must be evacuated to 1000 microns to eliminate con-
tamination and moisture in the system.
Table 3 — Physical Data
UNIT 40QN
018
024
OPERATING WEIGHT
(lb)
39
43
REFRIGERANT
R-22 with AccuRater
T
Control or TXV
FAN
Rpm
1120
1470
Nominal Cfm
(High Speed)
540
550
COIL
Rows
2
3
Face Area (sq ft)
2.56
2.56
Fins/in.
15.9
18.1
Number of Circuits
2
3
CONNECTIONS (MPT)
Suction (in.) Flare
5
⁄
8
Liquid (in.) Flare
3
⁄
8
Condensate Drain
5
⁄
8
LINE SIZES
Suction (in.)
5
⁄
8
Liquid (in.)
3
⁄
8
Condensate Drain
5
⁄
8
TXV —
Thermostatic Expansion Valve
(38HDS only)
Table 4 — Required Piston Sizes for AccuRater Metering Device
OUTDOOR
UNIT 38
INDOOR
UNIT 40QN
INDOOR
PISTON
INDOOR
PISTON TYPE
OUTDOOR
PISTON
OUTDOOR
PISTON TYPE
REQUIRED SYSTEM
CHARGE (lb)*
HDC018
B018
49
B
N/A
N/A
4.6
HDC024
B024
57
B
N/A
N/A
5.3
BK018
E018
51
B
47
B
5.0
BK024
E024
59
B
52
B
5.1
LEGEND
N/A —
Not Applicable
TXV —
Thermostatic Expansion Valve
*Charge amount determined based on 25 ft of line. Check charge for longer lines using superheat method. See 38HDC and BK installation, start-up,
and service instructions for system charging procedures.
NOTE: The 38HDS systems do not use the AccuRater device. The 38HDS systems have a TXV in the condensing unit for refrigerant metering and
control.
NOTE: Arrow on AccuRater body points in
free flow direction away
from the coil.
Fig. 9 — AccuRater Metering Device in Liquid
Line (Bypass Type Components)
Fig. 10 — AccuRater Metering Device at Service
Valve (Bypass Type Components)
6