Thermo Pride C Premiere Series - Manual (Page 13)

INITIAL START UP OF OUTDO
er), attempts to operate the air conditioner and take gauged pressure readings
may be unsuccessful, as unusually low pressures will be observed on the suction line. This type of operation
OR CONDENSING UNIT
On cooler days (65
° F or low
may give the impression of an undercharged unit. Such is NOT necessarily the case. The low-pressure
ing so much
eat from the refrigerant. Sub-cooling occurs and results in very low pressures. Adding refrigerant in cold
h pressure limit during warm or
ot weather. Line pressures should not be taken for test purposes when the outdoor temperature is below 70
°
onditioner on a day of 45
° F or cooler.
temp. of 76– 78ºF is reached then
t must be between 8 –
is done by comparing the gauge temp.
n the suction line to the measured
temp. on the low side of the condenser. The
en increase charge.
e temperature of the liquid line leaving
ture.
ature will be about 10ºF lower than its gauge temperature.
the difference is less add charge. If the difference is greater remove charge. The system should run for
r condensing units are equipped with gauge ports to connect both liquid and
ction line pressure gauges. Refrigerant hoses must be the type which incorporate a "finger" to depress the
s
hort
rvice hoses are recommended to minimize refrigerant losses.
reading may exist because of the large condenser surface area and the cold ambient air remov
h
weather will result in an overcharged unit, which may then trip out on hig
h
F since a false reading may occur. Do not attempt to operate the air c
When an inside
superheat measuremen
10ºF. This
of R-410A o
difference is the superheat. If the superheat is less
that 8
ºF decrease charge. If the superheat
is more than 10ºF th
Another check on system charge, would be to
measure th
the condenser and it’s R-410A gauge tempera
For proper operation, the measured liquid temper
If
at least 10 minutes before rechecking.
All Thermo Pride outdoo
su
core. Connections may be made to ports at any time; even while unit is in operation. Follow EPA guideline
in connecting service equipment to refrigerant lines. For example: The use of quick connects and s
se
: Refrigerant is under pressure. Guard against refrigerant spraying into the face o
on skin. Always wear protective eq
r
uipment, i.e. safety glasses or goggles and gloves when working
with refrigerant.
: R-410a systems operate at higher pressures than R-22 systems. Do not use R-22
service equipment or components on R-410a equipment. Service equipment must be rated for R410a.
Line pressures on an operating air conditioning unit will vary with outdoor temperatures. As outdoor
temperatures rise, pressures will also rise. See pressure temperature chart for system line pressures at
different temperatures.
The suction pressure is the most significant when reading gauges. If a unit is suspected of low charge, unit
should be recharged using the suction pressure as a guide. Unit is fully charged when proper suction
pressure is obtained. Any additional refrigerant may cause damage or additional problems.
ABLE : APP E OP RATIN
Insi Temp O side T
T 1 ROXIMAT E G PRESSURES
de . vs. ut emp. vs. Liquid
Suction Press. Press.
INSIDE
TEMP.
SUCTION
PRESS.
OUTSIDE
TEMP.
LIQUID
PRESS
(ºF) (P.S.I.G.) (P.S.I.G.) (ºF)
65 106 70 266
70 117 75 286
72 121 80 308
74 126 85 331
76 131 90 354
80 140 95 380
85 154 100 406
90 168 105 434
13