Profroid SUPERCOLD SCH - System Operations and Checks

29
/
61
 Fan ch e cks
Direction of rot a tion
Check that the fans are rotating in the correct direction, i.e. drawing on the coil.
 P r e - S e tting And Checking of Safety S y st e ms
- Pre-set the HP/LP (compressor safely) pressure switches and test manually.
- Pre-set the HP regulation pressure switch and test manually..
The condensation pressure is regulated through a HP (High Pressure) pressure switch that starts the fan motors according to
the setting chosen.
Every possible measure should be taken in order to avoid short circuit. Maximum 15 cycles per hour.
Device
Elect .
S y mb
Function Fluid
Applic a ti
on
Recommended
settings
HP/LP
pressure
switch
HP/LP
Compressor
safety
d
e
v
i
c
e
R22
R404A
Positive
Negative
Cut out : 24 bar
Cut in : 18 bar
Compressor
safety
d
e
v
i
c
e
R22 Positive Cut out : 1 bar
Cut
i
n
:
3
b
a
r
R404A Positive Cut out : 1,5 bar
Cut in :4 bar
R404A Negative Cut out : 0,2 bar
Cut in : 1,5 bar
Important : The pressure sensors are on the compressor valves and the valve opening should be left connected to the circuit
( 1 /4 T) .
START - UP
 Start up of condensing unit
- Open all the valves (compressor suction and discharge in liquid bottle)
- Place an ammeter on one phase of the compressor
- Close the power circuit-breaker or the fan motor cut-outs.
- Start up compressor by switching the on/off switch to on.
The current increases to maximum and should decrease very rapidly. If this does not happen, stop the compressor to check and
find the fault.
The condenser fans should cut in automatically according to the pre-set set points.
 Remainder of ch a rg e
Fill up with the remainder very quickly.
An incomplete charge of fluid will cause considerable superheat and so abnormally high discharge temperatures.
OPERATING CHECKS
Shortly after start-up, the operating conditions of the equipment must be checked.
 C ompr e ssor
- The compressor must operate within its acceptable limits
(see Manufacturer's advice).
- Check on each compressor:
 Voltage