9.4. Thermal insulation of refrigerant piping
Be sure to give insulation work to refrigerant piping by covering high press. (liquid)
pipe and low press. (gas) pipe separately with enough thickness heat-resistant
polyethylene, so that no gap is observed in the joint between indoor unit and insu-
lating material, and insulating materials themselves. When insulation work is insuf-
ficient, there is a possibility of condensation drip, etc. Pay special attention to insu-
lation work to ceiling plenum.
[Fig. 9.4.1] (P.4)
A Steel wire
C Asphaltic oily mastic or asphalt
E Outer covering B
Glass fiber + Steel wire
Heat
insulation
Adhesive + Heat - resistant polyethylene foam + Adhesive tape
material A
Indoor
Vinyl tape
Outer
Floor exposed Water-proof hemp cloth + Bronze asphalt
covering B
Heat source
Water-proof hemp cloth + Zinc plate + Oily paint
Note:
•
When using polyethylene cover as covering material, asphalt roofing shall
not be required.
•
No heat insulation must be provided for electric wires.
[Fig. 9.4.2] (P.4)
A High press. pipe
B Low press. pipe
D Finishing tape
E Insulator
[Fig. 9.4.3] (P.4)
10. Wiring
10.1. Caution
1 Follow ordinance of your governmental organization for technical standard re-
lated 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 [2 in or more]) apart from power source wiring so that it is not influenced
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 heat source unit.
4 Give some allowance to wiring for electrical part box of indoor and heat source
units, because the box is sometimes removed at the time of service work.
5 Never connect the main power source to terminal block of transmission line. If
connected, electrical parts will be burnt out.
6 Use 2-core shield cable for transmission line. If transmission lines of different
systems are wired with the same multiplecore cable, the resultant poor trans-
mitting and receiving will cause erroneous operations.
7 Only the transmission line specified should be connected to the terminal block
for heat source unit transmission.
(Transmission line to be connected with indoor unit : Terminal block TB3 for
transmission line, Other : Terminal block TB7 for centralized control)
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 heat source units.
Connect this control line between the terminal blocks for centralized control.
(2-wire line with no polarity)
When conducting group operation in different refrigerant systems without con-
necting to the upper class controller, replace the insertion of the short circuit
connector from CN41 of one heat source unit to CN40.
9 Group is set by operating the remote controller.
10.2. Control box and connecting position of
wiring
1. Connect the indoor unit transmission line to transmission terminal block (TB3),
or connect the wiring between heat source units or the wiring with the central
control system to the central control terminal block (TB7).
When using shielded wiring, connect shield ground of the indoor unit transmis-
sion line to the ground screw (
) and connect shield ground of the line be-
tween heat source units and the central control system transmission line to the
shield (S) terminal of the central control terminal block (TB7) shield (S) termi-
nal. In addition, in the case of heat source units whose power supply connector
CN41 has been replaced by CN40, the shield terminal (S) of terminal block
(TB7) of the central control system should also be connected to the ground
screw (
).
12
B Piping
D Heat insulation material A
C Electric wire
Penetrations
[Fig. 9.4.4] (P.4)
<A> Inner wall (concealed)
<C> Outer wall (exposed)
<E> Roof pipe shaft
<F> Penetrating portion on fire 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 filling 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 materi-
als 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
specifications:
ø6.35 to 25.4 mm [1/4 to 1 in]
Thickness
10 mm min. [13/32 in min]
Temperature Resistance
*
Installation of pipes in a high-temperature high-humidity environment, such as
the top floor of a building, may require the use of insulation materials thicker
than the ones specified in the chart above.
*
When certain specifications presented by the client must be met, ensure that
they also meet the specifications on the chart above.
Fix the wiring securely in place with the cable strap at the bottom of the termi-
nal block so that the external force if not applied to the terminal block. External
force applied to the terminal block may damage the block and short-circuit,
ground fault, or fire may result.
[Fig. 10.2.1] (P.4)
A Power source
C Ground screw
2. Conduit mounting plates (ø27 [1-3/32 in]) are being provided. Pass the power
supply and transmission wires through the appropriate knock-out holes, then
remove the knock-out piece from the bottom of the terminal box and connect
the wires.
3. Fix power source wiring to terminal box by using buffer bushing for tensile
force (PG connection or the like).
4. Narrow the opening by using a conduit to keep small animals out.
10.3. Wiring transmission cables
1 Types of control cables
1. Wiring transmission cables
•
Types of transmission cables: Shielding wire CVVS or CPEVS or MVVS
•
Cable diameter: More than 1.25 mm
•
Maximum wiring length: Within 200 m [656 ft]
•
Maximum length of transmission lines for centralized control and indoor/out-
door transmission lines (Maximum length via indoor units): 500 m [1640 ft]
MAX
The maximum length of the wiring between power supply unit for transmission
lines (on the transmission lines for centralized control) and each outdoor unit
and system controller is 200 m [656 ft].
2. Remote control cables
•
M-NET Remote Controller
Sheathed 2-core cable (unshielded)
Kind of remote control cable
Cable diameter
0.3 to 1.25 mm
(0.75 to 1.25 mm
When 10 m [32ft] is exceeded, use cable with
Remarks
the same specifications as 1. Wiring transmis-
sion cables.
•
MA Remote Controller
Kind of remote control cable
Sheathed 2-core cable (unshielded) CVV
0.3 to 1.25 mm
Cable diameter
(0.75 to 1.25 mm
Remarks
Within 200 m [656ft]
*
Connected with simple remote controller.
<B> Outer wall
<D> Floor (waterproofing)
B Heat insulating material
D Caulking material
F Waterproofing laye
H Lagging material
Pipe size
ø28.58 to 38.1 mm [1-1/8 to 1-1/2 in]
15 mm min. [19/32 in min]
100 °C [212 °F] min.
B Transmission line
2
[AWG16]
2
[AWG22 to 16]
2
[AWG18 to 16])*
2
[AWG22 to 16]
2
[AWG18 to 16])*