Thermal Insulation Of Refrigerant Piping; Wiring (For Details, Refer To The Installation Manual Of Each Unit And Controller.); Caution; Control Box And Connecting Position Of Wiring - Mitsubishi Electric PURY-P-YHM-A Installation Manual

10.4. Thermal insulation of refrigerant
piping
Be sure to add insulation work to refrigerant piping by covering high-pressure
pipe and low-pressure pipe separately with enough thickness heat-resistant
polyethylene, so that no gap is observed in the joint between indoor unit and
insulating material, and insulating materials themselves. When insulation work is
insuf¿ cient, there is a possibility of condensation drip, etc. Pay special attention
to insulation work in the ceiling plenum.
[Fig. 10.4.1] (P.7)
A Steel wire
C Asphaltic oily mastic or asphalt
E Outer covering B
Heat Glass ¿ ber + Steel wire
insulation
Adhesive + Heat - resistant polyethylene foam + Adhesive tape
material A
Indoor Vinyl tape
Outer
Floor exposed Water-proof hemp cloth + Bronze asphalt
covering B
Outdoor Water-proof hemp cloth + Zinc plate + Oily paint
Note:
• When using polyethylene as a covering material, asphalt roo¿ ng shall
not be required.
• No heat insulation must be provided to electric wires.
[Fig. 10.4.2] (P.7)
A High-pressure pipe B Low-pressure pipe C Electric wire
D Finishing tape E Insulator
[Fig. 10.4.3] (P.7)

11. Wiring (For details, refer to the installation manual of each unit and controller.)

11.1. Caution

1 Follow ordinance of your governmental organization for technical standard
related to electrical equipment, wiring regulations and guidance of each
electric power company.
2 Wiring for control (hereinafter referred to as transmission line) shall be (5
cm or more) apart from power source wiring so that it is not inÀ uenced by
electric noise from power source wiring (Do not insert transmission line and
power source wire in the same conduit).
3 Be sure to provide designated grounding work to the outdoor unit.
4 Give some allowance to wiring for the electrical control box on the indoor
and outdoor units, because these boxes are sometimes removed at the time
of service work.
5 Never connect the main power source to the terminal block of the
transmission line. If connected, electrical parts will burn out.
6 Use 2-core shield cable for the transmission line. If transmission lines of
different systems are wired with the same multiplecore cable, the resultant
poor transmitting and receiving will cause erroneous operations.
7 Only the transmission line speci¿ ed should be connected to the terminal
block for outdoor unit transmission.
Erroneous connection does not allow the system to operate.
8 In the case of connecting with an upper class controller or to conduct group
operation in different refrigerant systems, the control line for transmission is
required between the outdoor units in different refrigerant systems.
Connect this control line between the terminal blocks for centralized control
(2-wire line with no polarity).
9 Grouping is set by operating the remote controller.
11.2. Control box and connecting position
of wiring
1 Outdoor unit
1. Remove the front panel of the control box by removing the 4 screws and
pushing it up a little before pulling it out.
2. Connect the indoor - outdoor transmission line to the terminal block (TB3) for
the indoor - outdoor transmission line.
If multiple outdoor units are connected in the same refrigerant system, daisy-
chain TB3 (M1, M2, Terminal) on the outdoor units. Connect the indoor -
outdoor transmission line for the outdoor units to TB3 (M1, M2,
of only one of the outdoor units.
18
B Piping
D Heat insulation material A
Terminal)
Penetrations
[Fig. 10.4.4] (P.7)
<A> Inner wall (concealed)
<C> Outer wall (exposed)
<E> Roof pipe shaft
<F> Penetrating portion on ¿ re limit and boundary wall
A
Sleeve
C
Lagging
E
Band
G
Sleeve with edge
I Mortar or other incombustible caulking
J
Incombustible heat insulation material
When ¿ lling a gap with mortar, cover the penetration part with steel plate so
that the insulation material will not be caved in. For this part, use incombustible
materials for both insulation and covering. (Vinyl covering should not be used.)
• Insulation materials for the pipes to be added on site must meet the following
speci¿ cations:
Outdoor unit High-pressure pipe
-BC controller Low-pressure pipe
BC controller Pipe size 6.35 mm to 25.4 mm
-indoor unit Pipe size 28.58 mm to 38.1 mm 15 mm or more
* Installation of pipes in a high-temperature high-humidity environment, such
as the top À oor of a building, may require the use of insulation materials
thicker than the ones speci¿ ed in the chart above.
* When certain speci¿ cations presented by the client must be met, ensure that
they also meet the speci¿ cations on the chart above.
3. Connect the transmission lines for centralized control (between the
centralized control system and the outdoor unit of different refrigerant
systems) to the terminal block for centralized control (TB7). If the multiple
outdoor units are connected to the same refrigerant system, daisy-chain TB7
(M1, M2, S Terminal) on the outdoor units in the same refrigerant system.
(*1)
*1: If TB7 on the outdoor unit in the same refrigerant system is not daisy-
chained, connect the transmission line for centralized control to TB7 on
the OC (*2). If the OC is out of order, or if the centralized control is being
conducted during the power supply shut-off, daisy-chain TB7 on the OC
and OS (In the case that the outdoor unit whose power supply connector
CN41 on the control board has been replaced with CN40 is out of order
or the power is shut-off, centralized control will not be conducted even
when TB7 is daisy-chained).
*2: OC and OS of the outdoor units in the same refrigerant system are
automatically identi¿ ed. They are identi¿ ed as OC and OS in descending
order of capacity (If the capacity is the same, they will be in ascending
order of their address number).
4. In the case of indoor-outdoor transmission line, connect the shield ground to
the grounding terminal ( ). In the case of transmission lines for centralized
control, connect it to the shield terminal (S) on the terminal block for
centralized control (TB7). Furthermore, in the case of the outdoor units
whose power supply connector CN41 is replaced with CN40, short circuit the
shield terminal (S) and the grounding terminal (
5. Fix the connected wires securely in place with the cable strap at the bottom
of the terminal block. External force applied to the terminal block may
damage it resulting in a short circuit, ground fault, or a ¿ re.
[Fig. 11.2.1] (P.8)
A Power source
C Earth screw
[Fig. 11.2.2] (P.8)
A Cable strap
C Transmission cable
2 Conduit tube installation
• Close by hammering the knockout holes for the conduit tube located on the
base and the bottom part of the front panel.
• When installing the conduit tube directly through the knockout holes, remove
the burr and protect the tube with masking tape.
• Use the conduit tube to narrow down the opening if there is a possibility of
small animals entering the unit.
<B> Outer wall
<D> Floor (waterproo¿ ng)
B
Heat insulating material
D
Caulking material
F
Waterproo¿ ng layer
H
Lagging material
10 mm or more
20 mm or more
10 mm or more
) in addition to the above.
B Transmission line
B Power source cable