Johnson Controls York VIR 40A, Руководство по установке

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11 GB
the units should be as short as possible. The
maximum admissible distances to the circuit
and the standard pipe diameter are indicated
in the tables below (without changing the
pipe outlet diameter of the units).
Pipes to be used
When installing the pipes that join the two
units, take special care in checking that the
pipes used are kept clean and dry prior to
installation. It is advisable to take the follow-
ing recommendations into account:
- Use cooling quality copper pipes only
(K or L, S/ASTMB88 type).
- Do not work outside when raining.
- The ends of the pipes should remain
closed throughout the installation.
- Do not leave the filter-dryer nor the com-
pressor out in the open.
- When welding, use low melting point
rods. These should contain 5% silver
minimum.
- While welding and as long as the pipe
remains hot, maintain a current of dry
nitrogen so as to avoid rust and scaling
inside the pipe. This could cause contami-
nation and obstructions.
- Do not use strippers at the copper-copper
joints.
- Connection to the units should be carried
out by using the flaring method.
Insulation of refrigerant pipes
Since the joining pipes between the distribu-
tor and the coil are installed in the outdoor
unit, both the larger and the smaller diameter
pipes are on the relative low pressure side
of the system.
Consequently, to avoid condensed water
from the pipes from dripping on the floor,
both must be insulated with adequate insu-
lation. The thickness of same should be at
least 8 mm.
Draining and drying
Air does not act as refrigerant because it
cannot be liquefied by the compressor.
The air and humidity that remain in the cool-
ing system have undesirable effects, such
as those listed below. Consequently, they
should be eliminated completely.
- High pressure increases.
- Consumed power increases.
- The performance of the unit decreases.
- The water contained in the air can freeze
and block the capillaries.
- The water can cause the corrosion of
certain parts of the circuit and the dete-
rioration of the compressor.
Process
In each circuit:
1- Connect a vacuum pump and a service
pressure gauge.
2- Carry out a vacuum of up to 50 microns,
minimum.
3- Check for leaks.
Refrigerant charge
The refrigerant charge is calculated with a
pipe length of 7.5 meters. See the refriger-
ant charge in the table below, by models
and size.
Refrigerant charge and pipe diameters
Model
Nominal charge
R-410A
(Kg)
Number of circuits Gas line diameter Liquid line diameter
Additional charge, grs.
(per meter)
VCH 20A/VIR 25A 8.5 1 1 1/8" (28.5 mm) 1/2" (12.7 mm) 112
VCH 25A/VIR 25A 8.5 1 1 1/8" (28.5 mm) 1/2" (12.7 mm) 112
VCH 30A/VIR 40A
12 1 1 1/8" (28.5 mm) 5/8" (15.87 mm) 170
VCH 40A/VIR 40A 12 1 1 1/8" (28.5 mm) 5/8" (15.87 mm) 170
VCH 45A/VIR 45A 9.5 x 2 2 1 1/8" (28.5 mm) 1/2" (12.7 mm) 112
VCH 60A/VIR 60A 10.5 x 2 2 1 1/8" (28.5 mm) 5/8" (15.87 mm) 170
VCH 75A/VIR 75A
15 x 2 2 1 3/8" (35 mm) 7/8" (22 mm) 333
VCH 90A/VIR 90A 16 x 2 2 1 3/8" (35 mm) 7/8" (22 mm) 333