Velp Scientifica
– UDK139 Operating Manual
10004762/B5
50
8.2.
Extraordinary maintenance
Extraordinary maintenance operations not included in this manual and the
servicing of internal parts, must be carried out by persons expressly authorized by
VELP Scientifica.
In order to reduce the risks arising from contact with reagents or solutions, the use
of suitable personal protective equipment (gloves, etc.) is recommended.
Periodic maintenance
Clean the sodium hydroxide tubes (NaOH). Every 500 analyses.
Clean the filters. Every 500 analyses.
Replace the test tube connection. Every 1000 analyses.
NOTE
: Extraordinary maintenance is recommended every 500 or 1000 analyses.
The counters can be reset and the date of last maintenance entered in
"Maintenance" menu.
Operations to be performed only when necessary:
Replace fuses
Clean the condenser
Clean the inside of the safety guard
8.2.1. Periodic maintenance
Cleaning the sodium hydroxide tubes
(Frequency: every 500 analyses)
These tubes must be kept full at all times. When the sodium hydroxide solution
comes into contact with air, crystals are formed which obstruct the tubes and
jeopardize the correct functioning of the internal parts.
The tubes must be cleaned as part of extraordinary maintenance operations as
follows:
Place an empty test-tube in the unit
Place the end of the sodium hydroxide with with level sensor in a vessel
containing warm distilled water (approx. 40°C).
Following the procedure for filling the tubes manually (see chapter 4.6.1),
fill the circuit with at least 1 litre of water.
Using the same procedure, fill the tubes with sodium hydroxide solution.
Cleaning the filters
(Frequency: Every month or after 500 analyses)
The unit is fitted with 4 filters to remove particles, sediment or any other foreign
bodies from the tap water and reagents.
NOTE:
Disconnect the unit from the electric power supply and water supply
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