York SCOH-070K Installation Instructions Manual page 12

- Do not leave dryer filters or the compres-
sor out in the open air.
- For welding use low melting point rods
with a 5% silver content, minimum.
- When welding and as long as the tubing
is hot, maintain a flow of dry nitrogen so
as to avoid internal rusting and scaling
that could cause contamination and ob-
struction.
- Do not use strippers on copper-copper
joints.
- Connection to the units should be carried
out by means of the flaring method.
Insulation of refrigerant tu-
bing
Due to the fact that the capillary tubing is in-
stalled in the outdoor unit, both the larger as
well as the smaller diameter tubes are in the
relative low pressure side of the system.
Consequently, to avoid condensed water
dripping on the floor, both tubes should be
insulated adequately. The thickness of same
should be at least 8 mm.
Emptying and dehydrating
Air does not act as a refrigerant since it can-
not be liquefied by the compressor. Any air
and humidity remaining in the cooling sys-
tem has undesirable effects, as indicated
below.
Consequently, they should be eliminated
completely.
- High pressure increases.
- Consumed power supply increases.
- Equipment performance decreases.
- Water contained in the air could freeze
and block the capillaries.
- Water can cause corrosion of certain parts
of the circuit, and deterioration of the com-
pressor.
Process
In each circuit:
1- Connect a vacuum pump and service
pressure gages.
2- Carry out a vacuum of up to at least
50 microns.
3- Detect leaks.
Refrigerant load
The refrigerant load is calculated for a
tubling length of 7.5m. See refrigerant load
table, in accordance with model and size.
Adjusting refrigerant load
For tubing lengths longer or shorter than
7.5 m., the nominal refrigerant load should
be increased or decreased by the grams
indicated in the following table, in accord-
ance with the increase or decrease in the
length of the liquid tubing.
Make sure the refrigerant load is correct by
measuring overheating. In normal summer
conditions, 5 °K is correct.
12
Detecting leaks
Once load is complete, replace the caps on
the charging valves and check for leaks.
Application of R-407-C refrige-
rant
Due to the characteristics of R-407-C
refrigerant, its evaporating, condensing
and discharge temperatures, its high
operating pressure in the units and the
specific requirements needed for efficient
operation (free from dampness and dirt), a
specially trained technical team with the
corresponding certification is required for
handling same.
R-407-C (Mixture of 3
refrigerants: HFC-32 + HFC-
125 + HFC-134a)
Standard compressor
P.O.E. oil
Charge in liquid phase
(by weight)
T° Evaporation with
displacement (7°C)
High vacuum 50 microns in 2 stages
Detection of difficult leaks
(requires detector
adapted to R-407-C)
Refrigerating piping
Model
SCOC-076K & 150K
SCOH-070K, 076K & 150K
SCOC-090K, 180K
SCOH-090K, 120K, 180K
SCOC-240K
SCOH-300K
GB
Wiring
In all cases, the established National regu-
lations should be followed. Each unit is sup-
plied with a control box to which the po-
wer supply will be connected by means of
a fused main switch or an automatic
switch.
Thermostat connection
For connecting thermostat to control board,
2
10 x 0.22 mm screened communication
cable should be used.
Configuration of the electronic
board
For start-up after the accessories are in-
stalled, connect power supply to the unit. To
have the electronic board respond in accord-
ance with the accessories installed, press
the "test" button a few seconds, until the red
LED goes out.
The "test" button should be pressed only
when the board is under electric current. If
pressed and held without any current at the
board, and then the power supply is con-
nected, the microprocessor will lose its con-
figuration and the board assembly will have
to be replaced.
Scroll compressors, rotational
direction
The Scroll compressors, just like the fans,
operate correctly in only one rotational
direction. Upon starting the unit up, this
rotational direction should be checked. If it is
not correct:
- The compressor does not compress.
- It makes abnormal noise.
- The consumption of amps is low.
- It overheats.
The compressor should not be allowed to
operate under these conditions. In this case,
change the order of two of the three power
supply wires going to the compressor.
Gas line diameter
1
1 / " (28.5 mm)
8
1 3 / " (35 mm)
8
Liquid line diameter
1/2" (12.7 mm)
5/8" (15.87 mm)
7/8" (22 mm)