Electrical Connections; Thermostat Connection - Johnson Controls YORK VCH 20A Instructions D'installation

Maximum length (L): This is the sum of
the lengths of all horizontal and vertical
straight sections in one single direction
(liquid or gas).
Maximum equivalent length (L
the sum of the lengths of all straight sections
of the interconnecting pipes (liquid or gas)
in one single direction, plus the equivalent
length of the accessories (basically elbows
and bends). The equivalent length due to
elbows and bends can be seen in the fol-
lowing table:
Accessory equivalent lengths in meters
Elbow (short
Ext. pipe diameter
radius)
3/8" 0.3
1/2" 0.4
5/8" 0.5
3/4" 0.5
7/8" 0.
1 - 1/8" 0.7
1 - 3/8" 1
1 - 5/8" 1.2
Note: The elbows and 45° bends (used in siphons, for example)
have half the equivalent length of the 90° bends.
Example:
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L = 2 + 3 + 3 +  + 4 + 7 +  + = 31
31 < therefore, 50% is correct
To calculate the equivalent length of the interconnecting pipes
we use, just as we would for the pressure drop, the data of one
of the liquid lines; that is to say 1/2" outer diameter. As we see
in the diagram, there 4 elbows with an equivalent length of 0.5
m. (as per table) and 2 bends of 0.4 (as per table). Therefore,
to make sure that the pipe equivalent length is not over the
admissible maximum, we have:
L = 2 + 3 +  + 4 + 7 +  + 4 (0.5) + 2 (0.4) = 22.8 m.
E
33.8 < therefore, 0 % is correct
18
Adjusting the refrigerant charge
For lengths over or under 7.5 m., the nominal
charge should be increased or decreased
by the grams indicated in the corresponding
table, depending upon whether the length
): This is
of the liquid line has been increased or
E
decreased.
Check to see whether the refrigerant is cor-
rect by measuring overheating. In normal
summer conditions between 5 and 10°K
is correct.
Service valves
90° bend (long
radius)
0.2
0.3
0.4
0.4
0.5
0.
0.7
0.8
There are 3/8" suction and discharge service
valves that are useful for a quick and correct
total drain.
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Checking for leaks
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Once the charging through the1/4" nozzles
located in the circuit is complete, check for
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Application of R-410A refriger-
ant
Due to the characteristics of the refrigerant,
its evaporation, condensation and discharge
temperature, its high operating pressure
in the units, and the specific requirements
needed for efficient operation (free of humid-
ity and dirt), it is obligatory to have a special-
ized group of technicians, with a certificate
of aptitude, handle the refrigerant.
Wiring

Electrical connections

The established national regulations must
be followed at all times.
Each unit is supplied with a circuit board
to which the power supply is connected by
means of a fuse main switch or an automatic
switch.
This circuit board includes a phase detec-
tor to insure the electric sequence is R-S-T.
Should this not be the case, the electronic
control board will not be powered and the
unit will not operate. In this case, interchange
two of the main power supply intake of the
unit.
Connection of the indoor fan
VIR 25A to 90A
Should the phase sequence (R-S-T) be cor-
rect but the indoor fan turns in the opposite
direction, interchange two phases at the
bottom of the fan contactor.

Thermostat connection

To connect the thermostat to the control
board use a screened 10 x 0.22 communi-
cation cable.
Setting the electronic board
For start-up and once the accessories are
installed, power the units. To have the elec-
tronic board respond in accordance with
the accessories installed, press the "test"
key for about two seconds, until the red
LED goes off.
Selecting cool only operation
To set the VCH outdoor unit in cool only
mode set, on the YKlon A1 board, micros-
witch (S1) No. 5 to position ON. It is neces-
sary to turn the board power supply of to
read out the new configuration.
Rotational direction of the
Scroll compressors
The Scroll compressors and the fans oper-
ate correctly in one single rotational direc-
tion. When turning the unit on, make sure
the rotational direction is correct.
If it is not correct:
- The compressor does not compress.
- It makes a strange noise.
- The consumption of amperage is re-
- Excessive overheating.
All motors are factory wired to rotate in the
correct direction.
WARNING
may also exist.
Therefore, make sure all cables are con-
nected tightly.
Do not power or operate the unit until
all pipes and electrical connections are
made.
Make sure the power supply is connected
correctly to the units, as shown in the wiring
diagrams.
GB
duced.
Loose cables can cause over-
heating of terminals or incorrect
operation of the unit. Fire hazards