Thermal Insulation Of Refrigerant Piping - Mitsubishi Electric Y Série Manuel D'installation

10.4. Thermal insulation of refrigerant piping

Be sure to add insulation work to refrigerant piping by covering liquid pipe and gas
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 insufficient, there is a possibility of
condensation drip, etc. Pay special attention to insulation work in the ceiling ple-
num.
[Fig. 10.4.1]
C
B
A
D
E
A Steel wire
C Oily mastic asphalt or asphalt
E Outer covering B
Heat Glass fiber + 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 cover as covering material, asphalt roofing shall
not be required.
• No heat insulation must be provided for electric wires.
[Fig. 10.4.2]
B
A
C
D
E
A Liquid pipe B Gas pipe
D Finishing tape E Insulator
[Fig. 10.4.3]
B Piping
D Heat insulation material A
E
E
A
B
D
C Electric wire
Penetrations
[Fig. 10.4.4]
<A> Inner wall (concealed)
A B
<C> Outer wall (exposed)
E
B
I
<E> Roof pipe shaft
G
D
B
H
F
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]
10 mm min. [13/32 in min.]
Thickness
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.
(Unit: mm [in])
<B> Outer wall
D
C
A B
<D> Floor (waterproofing)
D
F
G
B
<F> Penetrating portion on fire limit and
boundary wall
I
J
A
1000 1000
[39-3/8] [39-3/8]
B Heat insulating material
D Caulking material
F Waterproofing layer
H Lagging material
Pipe size
ø28.58 to 41.28 mm [1-1/8 to 1-21/32 in]
15 mm min. [19/32 in min.]
100°C min. [212°F min.]
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