Lennox 13ACX, Инструкция по установке и обслуживанию

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Page 31
13ACX SERIES
DO NOT CHARGE UNIT
(Results of charging at low
temperatures not reliable)
START: Measure outdoor ambient temperature
USE WEIGH‐IN METHOD
Weigh‐in or remove refriger­
ant based upon line length
1. Confirm proper airflow across coil using figure 17.
2. Compare unit pressures with normal operating
pressures provided on applicable charging sticker
as reference in table 4..
3. Set thermostat to call for heat (must have a cooling
load between 70‐80ºF (21-26ºC).
4. Connect gauge set.
5. When heat demand is satisfied, set thermostat to
call for cooling.
6. Allow temperatures and pressures to stabilize.
7. Record outdoor ambient temperature:
AMBº =_________
8. Record liquid line temperature:
LIQº = __________
9. Subtract to determine approach (APPº):
LIQº_____ - AMBº _____ = APPº_____
10. Compare results with table below.
Figure 20. HFC-410A Approach TXV Charge
ABOVE or
BELOW
If value is greater than
shown (high approach),
add refrigerant; if less
than shown (liquid
temperature too close to
ambient temperature,
low approach), remove
refrigerant.
If refrigerant is added
or removed, retest to
confirm that unit is
properly charged.
64ºF
(17.7ºC) and
Below
65ºF
(18.3ºC) and
Above
APPROACH TXV
See Table 4 on page 33 to determine
which charging sticker to use.
DO NOT CHARGE UNIT
(Results of charging at low
temperatures not reliable)
START: Measure outdoor ambient temperature
USE WEIGH‐IN METHOD
Weigh‐in or remove refrigerant
based upon line length
BLOCK OUTDOOR COIL: [sometimes necessary with
lower temperatures] Use cardboard or plastic sheet to
restrict the airflow through the outdoor coil to achieve
pressures from 325-375 psig (2240-2585 kPa).
Higher
pressures are needed to check charge. Block equal
sections of air intake panels and move coverings sideways
until the liquid pressure is in the above noted ranges.
If value is
MORE than
shown, remove
refrigerant.
1. Confirm proper airflow across coil using figure
17.
2. Compare unit pressures with normal operating
pressures provided on applicable charging
sticker as reference in table 4.
3. Set thermostat to call for heat (must have a
cooling load between 70‐80ºF (21-26ºC)
4. Connect gauge set
5. Measure outdoor ambient temperature
6. When heat demand is satisfied, set thermostat to
call for cooling
7. Allow temperatures and pressures to stabilize.
NOTE - If necessary, block outdoor coil to
maintain 325 - 375 psig.
8. Record liquid line temperature:
LIQº = ______
9. Measure liquid line pressure and use the value to
determine saturation temperature (see table 3):
SATº = ______
10. Subtract to determine subcooling (SCº):
SATº_____ - LIQº _____ = SCº _____
11. Compare results with table below.
Figure 21. HFC-410A Subcooling TXV Charge
MORE or
LESS
If value is LESS
than shown, add
refrigerant.
If refrigerant is
added or removed,
verify charge using
the
Approach
Method .
ABOVE or
BELOW
64ºF
(17.7ºC) and
Below
65ºF
(18.3ºC) and
Above
CARDBOARD OR PLASTIC SHEET
SUBCOOLING TXV
See Table 4 on page 33 to determine
which charging sticker to use.