ARUF ASPT Installation Instructions

9
7.7 Thermal Expansion Valve Syst em Adj ust ment
Run t he syst em at Cooling f or 10 minut es unt il ref rigerant
pressures st abilize. Use t he f ollowing guidelines and met h-
ods t o check unit operat ion and ensure t hat t he ref rigerant
charge is wit hin limit s. Charge t he unit on low st age.
1. Purge gauge lines. Connect service gauge manif old t o
base-valve service port s.
2. Temporarily inst all a t hermomet er on t he liquid line
at t he liquid line service val ve and 4-6" f rom t he com-
pressor on t he suct ion line. Ensure t he t hermomet er
makes adequat e cont act and is insulat ed f or best pos-
sible readings. Use liquid line t emperat ure t o det er-
mine subcooling and vapor t emperat ure t o det ermine
superheat .
3. Check subcooling and superheat . Syst ems wit h TXV ap-
plicat ion should have a subcooling of 7 t o 9ºF and su-
perheat of 7 t o 9 ºF.
a. If subcooling and superheat are low, adj ust TXV t o
7 t o 9 ºF superheat , t hen check subcooling.
NOTE: To adj ust superheat , t urn t he valve st em clockwise
t o increase and count er clockwise t o decrease.
b. If subcooling is low and superheat is high, add charge
t o raise subcooling t o 7 t o 9ºF t hen check superheat .
c. If subcooling and superheat are high, adj ust TXV
valve t o 7 t o 9 ºF superheat , t hen check subcooling.
d. If subcooling is high and superheat is low, adjust
TXV valve t o 7 t o 9 ºF superheat and remove charge t o
lower t he subcooling t o 7 t o 9ºF.
NOTE: Do NOT adj ust t he charge based on suct ion pressure
unless t here is a gross undercharge.
4. Disconnect manif old set , inst allat ion is complet e.
NOTE: Check t he Schrader port s for leaks and t ight en valve
cores if necessary. Inst all caps f inger-t ight .
SUBCOOL FORMULA =
SAT. LIQUID LINE TEMP. - LIQUID LINE TEMP.
SUPERHEAT FORMULA =
SUCT. LINE TEMP. - SAT. SUCT. TEMP.
NOTE: Expansion val ve syst em in ASPT models are already
t uned f or 16 SEER single st age Heat Pump, adj ust ment of
Expansion valve syst em is required in case subcool, superheat
does not mat ch t o Sect ion 7. 6. 3 above or when t hese models
are inst alled wit h any ot her out door models.
SUCTION PRESSURE
PSIG R-22 R-410A
50 26 1
52 28 3
54 29 4
56 31 6
58 32 7
60 34 8
62 35 10
64 37 11
66 38 13
68 40 14
70 41 15
72 42 16
74 44 17
76 45 19
78 46 20
80 48 21
85 50 24
90 53 26
95 56 29
100 59 31
110 64 36
120 69 41
130 73 45
140 78 49
150 83 53
160 86 56
170 90 60
SATURATED SUCTION PRESSURE
TEM PERATURE CHART
SATURATED SUCTION