Tetra Pak Hoyer Frigus 600, Руководство пользователя

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7-40
Tetra Pak
Hoyer
B F60 03 G 04
The trend to corrode or scale depends on the type
and amount of substances dissolved in water, the
acidity of the water and the temperature at which
it is used. It is recommended that users contact a
specialist firm capable of recommending and
supplying batching devices, substances, and
procedures suited to the specific cooling water
system in use.
This is particularly important in the case of water
towers, where temperature, evaporation and
continual ventilation with air in the environment
can generate waters which are particularly
polluted (by solid particles, algae, mineral salts,
micro-organisms, gases, etc.) and damaging for
the entire plant and the condenser in particular.
Keeping the condenser clean
When condensation temperature is excessive for
the conditions of operation in effect, it is time to
clean the condenser.
The condensation temperature must be between
28
°
C and 36
°
C. If the water temperature is less
than or equal to 28 ° C; about 3600 litres/hour of
water will be required at a temperature of 28 ° C.
Check that these conditions are met and that all
the rest is working properly before deciding that
the condenser needs cleaning.
If the condenser does need cleaning, contact a
qualified refrigerator technician who has the
equipment required to carry out chemical
cleaning.
WARNING:
Do not disassemble the condenser and
disconnect it from the coolant pipes for
cleaning.
The Frigus 600 is fitted with two connections
for cleaning the condenser: one inside the
machine, at the top of the condenser next to the
coolant gas pipe (washing solution intake) and
one on the outside halfway between the water
intake and outlet (washing solution outlet). Both
these connections are normally closed off.
Turn off the cooling water intake and outlet taps.
Use a closed washing circuit consisting of a
container and a centrifugal pump as shown in
the figure; connect the pump delivery to the
washing solution intake (top inside) through a
plastic hose. Connect another plastic hose to the
washing solution outlet (halfway on the outside)
to return solution to the container.
First let water run through to get rid of any solid
particles in the condenser.
Then prepare a suitable buffered solution (such
as Henkel P3 T288) according to the
manufacturer’s instructions and put it in the
container. Flush it through, following the
instructions for use, until the solution’s indicator
(colour change, pH, etc.) indicates that scale has
been removed. This may take a few hours.
WARNING:
Under no circumstances should strong
inorganic acids such as hydrochloric acid,
nitric acid, or sulphuric acid be used for any
reason. These acids are very dangerous and
could cause irreparable damage to the
condenser in only a few minutes.
Passivate and rinse according to the instructions;
remove pipes and close connections up again.
Open the cooling water intake and outlet taps
again, and check that water is circulating
normally with no leakage.
Thermostatic expansion valve
This valve is factory set during final testing to
optimise the dependability and performance of
the refrigerating plant.
The factory setting should not be changed for
any reason. If the machine is not working
properly, all parameters affecting performance
should be checked, such as the temperature of
incoming mix, wear on the scraper blades, and
correct circulation of condensation water.
•
If the refrigerating plant is not working as
well as it should do, the reason may be:
- insufficient condensation
- inefficient thermostat valve;
- dirty or blocked up filter on the line;
- hot gas solenoid valve blocked up or open,
- liquid solenoid valve blocked up or closed;