5156631-UIM-G-0417
Johnson Controls Unitary Products
7
8.
Pass the TXV temperature sensing bulb through the suction line
split grommet in the access panel.
9.
Install the TXV bulb to the vapor line near the cabinet, using the
bulb clamp(s) furnished with the TXV assembly. Ensure the bulb is
making maximum contact. See Figures 7 and 8, and accomplish
the following:
a.
If possible, install the temperature bulb on a horizontal run of
the vapor line. Ensure that the bulb is installed at a 10 o’clock
or 2 o’clock position.
b.
If bulb installation is made on a vertical run, ensure that the
bulb is a minimum 8 inches (23.3 cm) away from elbow com-
ing out of the coil. Position the bulb with the tail of the bulb at
the top, so that the bulb acts as a reservoir. See Figure 9.
c.
Bulb should be insulated using thermal insulation provided to
protect it from the effect of the ambient temperature. Cover
completely to insulate.
10. After line set is installed, leak test the system.
SECTION V: EVACUATION
If the coil has a stub out kit installed, evacuate the system to 500
microns or less. If a leak is suspected, leak test with dry nitrogen to
locate the leak. Repair the leak and test again.
To verify that the system has no leaks, simply close the valve to the
vacuum pump suction to isolate the pump and hold the system under
vacuum. Watch the micron gauge for a few minutes. If the micron
gauge indicates a steady and continuous rise, it’s an indication of a
leak. If the gauge shows a rise, then levels off after a few minutes and
remains fairly constant, it’s an indication that the system is leak free but
still contains moisture and may require further evacuation if the reading
is above 500 microns.
SECTION VI: SYSTEM CHARGE
To ensure that your unit performs at the published levels, it is important
that the indoor airflow is determined and refrigerant charge added
accordingly.
FIGURE 7:
TXV Bulb Installation
FIGURE 8:
Proper Bulb Location
T
X
V
B
U
LB
(W
rap
w
ith
insu
l
ation
.)
VAPOR
LIN
E
LI
QU
I
D
LIN
E
TV
X
EQUA
LIZ
ER
LIN
E
THERMA
L
E
X
PA
N
S
I
O
N
VA
L
VE
(
T
X
V
)
D
I
STR
IB
UTOR
B
OD
Y
A
0279-002
T
X
V
B
U
LB
(
Co
v
er
co
m
p
l
ete
ly
w
ith
insu
l
ation
.)
VAPOR
LIN
E
O
F LIN
E
SET
A
0269-002
C
L
AMP
A
DETAIL A
T
X
V
SE
N
S
ING B
U
LB
(
Pass
through
sp
l
it
ho
l
e
in
gro
mm
et
.)
VAPOR
LIN
E
N
UT
N
UT
B
u
lb
at
10
o
’
c
l
oc
k
position
.
B
u
lb
at
2
o
’
c
l
oc
k
position
.
SCRE
W
SCRE
W
C
L
AMP
FIGURE 9:
Vertical Temperature Bulb Orientation
CAUTION
Refrigerant charging should only be carried out by a licensed quali-
fied air conditioning contractor.
VAPOR
LIN
E
O
F LIN
E
SET
A
0378-002
C
L
AMP
T
X
V
TEMPERATURE
B
U
LB
TA
IL
E
N
D
UP
8” (23 3
c
m)
NOTE:
Ensure
b
u
lb
is
on
opposite
side
o
f
tu
b
ing
b
end
p
l
ane
.
!
