Selecting An Installation Site; About The Product; Installation Site; Securing Installation And Service Space - Mitsubishi Electric CITY MULTI CMB-WM108V-AA Installation Manual

2. Selecting an installation site

2.1. About the product

• This unit uses R410A-type or R32-type refrigerant.
• Indoor units that are all WP or all W models are connectable to the HBC
controller.
• Piping for systems using R410A or R32 may be different from that for systems
using conventional refrigerant because the design pressure in systems using
R410A or R32 is higher. Refer to the Data Book for more information.
• Some of the tools and equipment used for installation with systems that use other
types of refrigerant cannot be used with the systems using R410A or R32. Refer
to the Data Book for more information.
• Do not use the existing piping, as it contains chlorine, which is found in
conventional refrigerating machine oil and refrigerant. This chlorine will
deteriorate the refrigerant machine oil in the new equipment. The existing piping
must not be used as the design pressure in systems using R410A or R32 is
higher than that in the systems using other types of refrigerant and the existing
pipes may burst.

2.2. Installation site

• Install the unit in a place not exposed to rain. The HBC controller is designed to
be installed indoors.
• Install the unit with adequate space around it for servicing.
• Do not install the unit in a place that would result in the piping length restrictions
being exceeded.
• Check for refrigerant leaks before service.
- If the refrigerant leaks, fire may result.
• Install or store the unit in a place not exposed to direct radiant heat from other
heat sources or naked flame or other ignition sources.
• Do not install the unit in any oily steamy place or near any machine that
generates high frequencies. Doing so may cause a risk of fire, erroneous
operation or condensation.
• Depending on the operation conditions, HBC unit generates noise caused by
valve actuation, refrigerant flow, and pressure changes even when operating
normally. Therefore install the unit in places such as ceilings of corridor,
restrooms and plant rooms.
• Install indoor unit and HBC controller at least 5 m away from each other when
installed in a space with low background noise, e.g., hotel rooms.
• Allow enough space and access to ensure water piping, refrigerant piping and
electrical wiring can be easily connected.
• Avoid places exposed to the generation, inflow, accumulation or leakage of
flammable and sulfuric gases.
• Ensure a downward gradient of at least 1/100 for drain piping.
• Properly install the unit on a stable, load-bearing surface.
1. For hanging from the ceiling [Fig. 2.2.1] (P.2)
• Provide 2 inspection holes 450 mm square in the ceiling surface as shown in
[Fig. 2.3.1] (P.2).
• Install the unit in a suitable location (such as in the ceiling of a corridor or in the
bathroom etc) away from places regularly occupied. Avoid installing in the center
of a room.
• Ensure hanging bolts are of sufficient pull out strength.
Warning:
Be sure to install the unit in a place that can sustain the entire weight.
If there is a lack of strength, it may cause the unit to fall down, resulting in an
injury.
Caution:
• Be sure to install the unit horizontally.
Install the HBC level (less than 1° tilt), so that the drain pan can function
correctly.
• Install the HBC in an environment where the temperature in always above
0°C.
8

2.3. Securing installation and service space

1. For hanging from the ceiling
(This is a reference view showing the least installation space.)
[Fig. 2.3.1] (P.2)
<A> Top view
A Inspection hole
C Control box
E Water inlet
G Indoor unit side
*1 Dimensions with which pipe connection can be handled at site
Model name
CMB-WM108V-AA
CMB-WM1016V-AA
CMB-WM108V-AB
CMB-WM1016V-AB

2.4. Checking the installation site

Check that the difference of elevation between indoor and outdoor units and the
length of refrigerant piping are within the following limitations.
1. CMB-WM108V-AA + CMB-WM108V-AB
(CMB-WM1016V-AA) (CMB-WM1016V-AB)
[Fig. 2.4.1] (P.2)
A Outdoor unit
C Sub-HBC controller
E Less than H=50 m (when the outdoor unit is higher than HBC)
F Less than H1=40 m (when the outdoor unit is lower than HBC)
G Twinning pipe (field supply)
H Less than 110 m
J Up to three units for 1 branch port
Total capacity: less than 80 (but in same mode, cooling/heating)
K Less than 15 m
Item
Between outdoor unit and HBC
controller (refrigerant pipework)
Water pipework between indoor units and
HBC controller
Above outdoor unit
Between
indoor and
outdoor units
Below outdoor unit
Between indoor units and HBC controller
Between indoor units
Notes:
*1 Indoor units that are connected to the same branch joint cannot be
simultaneously operated in different operation modes.
2. CMB-WM108V-AA + CMB-WM108V-AB
(CMB-WM1016V-AA) (CMB-WM1016V-AB)
[Fig. 2.4.2] (P.2)
A Outdoor unit
C Sub-HBC controller
E Less than H=50 m (when the outdoor unit is higher than the indoor unit)
F Less than H1=40 m (when the outdoor unit is lower than the indoor unit)
G Twinning pipe (field supply)
H Less than 110 m
J Up to three units for 1 branch port
Total capacity: less than 80 (but in same mode, cooling/heating)
K Less than 15 m
M Less than 15 m
Item
Between outdoor unit and
HBC controller (refrigerant pipework)
Water pipework between indoor units
and HBC controller
Between HBC controllers
Above outdoor unit
Between
indoor and
outdoor units
Below outdoor unit
Between indoor units and HBC controller
Between indoor units
Between HBC controllers
<B> Front view
B Side of outdoor unit piping
D Side of indoor unit piping
F Service space
A B
1520 160
1800 300
1520 160
1520 160
B Main-HBC controller
D Indoor unit
I Less than 60 m
L Less than 15 m
(Unit: m)
Piping portion Allowable value
A 110 or less
f + g 60 or less
H 50 or less
H1 40 or less
h1 15 or less
h2 15 or less
B Main-HBC controller
D Indoor unit
I Less than 60 m
L Less than 15 m
(Unit: m)
Piping portion Allowable value
A + A + A 110 or less
1 2 3
f + g 60 or less
B 40 or less
H 50 or less
H1 40 or less
h1 15 or less
h2 15 or less
h3 15 or less