Positioning Considerations - Lennox Merit 13ACD-018 Installation Instructions Manual

METHOD 2:
Usethis method if theexisting outdoor u nitis equipped
with manualshut-offvalves,and plan on using new
HCFC-22 r efrigerant toflushthesystem,
IMPORTANT: Somesystemconfigurations maycontain
higher t hannormal r efrigerant charge duetoeitherlarge
internal coilvolumes, and/orlonglinesets, T hefollowing
conditions m aycausethecompressor tostopfunctioning:
Thefollowing devices couldprevent
f ull system charge
recovery into the outdoor unit:
• Outdoor unit's high or low-pressure switches if tripped
can cycled the compressor OFF.
• Compressor can stop pumping due to tripped internal
pressure relief valve.
• Compressor has internal vacuum protection that is
designed to unload the scrolls (compressor stops
pumping) when the pressure ratio meets a certain
value or when the suction pressure is as high as 20
psig. (Compressor suction pressures should never be
allowed to go into a vacuum. Prolonged operation at
low suction pressures will result in overheating of the
scrolls and permanent damage to the scroll tips, drive
bearings and internal seals),
Once the compressor can not pump down to a lower
pressure due to one of the above system conditions, shut
off the suction valve, Turn OFF the main power to unit and
use a recovery machine to recover any refrigerant left in
the indoor coil and line set.
Perform the following task:
1, Start the existing HCFC-22 system in the cooling
mode and close the liquid line valve,
2, Pump as much of the existing HCFC-22 refrigerant
with the compressor back into the outdoor unit until
you have reached the limitations of the outdoor
system, Turn the outdoor unit main power OFF and
use a recovery machine to remove the remaining
refrigerant in the system,
NOTE - It may be necessary to bypass the low pressure
switches if equipped to ensure complete refrigerant
evacuation.
3, When the low side system pressures reach 0 psig,
close the suction line valve,
4, Check gauges after shutdown to confirm that the
valves are not allowing refrigerant to flow back into the
low side of the system,
Perform the following task at the existing outdoor unit:
• Disconnect line set at the service valves.
• Disconnect electrical service at the disconnect switch.
• Remove old outdoor unit.
See Unit Dimensions on page 2 to sizing mounting slab,
platforms or supports. Refer to figure 7 for mandatory
installation clearance requirements.
* SEE NOTES BELOW THIS FIGURE FOR FURTHER DETAILS.
Figure 7. Installation Clearances
NOTES:
• Service clearance of 30 in. (762 mm) must be
maintained on one of the sides adjacent to the control
box.
• Clearance to one of the other three sides must be 36
in. (914 mm)
• Clearance to one of the remaining two sides may be
12 in. (305 mm) and the final side may be 6 in. (152
mm)
• 48 in. (1219 mm) clearance required on top of unit.
• A clearance of 24 in. (610 mm) must be maintained
between two units
POSITIONING CONSIDERATIONS
CAUTION
Consider the following when positioning the unit:
• Some localities are adopting sound ordinances based
on the unit's sound level registered from the adjacent
property, not from the installation property. Install the
unit as far as possible from the property line.
• When possible, do not install the unit directly outside
a window. Glass has a very high level of sound
transmission. For proper placement of unit in relation
to a window see the provided illustration in figure 8.
INSTALL UNIT AWAY _ _I
FRO W
TWO 90 ° ELBOWS INSTALLED
IN LINE SET WILL REDUCE _ "_"_
LINE SET VIBRATION.
Figure 8. Outside Unit Placement
Page 5
13ACD SERIES