Preventive Maintenance; Rinsing The Chemical Supply/Injector System; Deliming; Coupling - Nilfisk FOOD Hybrid MU421 Instrucciones De Uso

9.3. Preventive maintenance

Depending on usage, maintenance should be un-
dertaken by an authorised service engineer at least
once a year in order to prevent defects and failure of
operation. Authorised engineers are persons who due
to their skills and experience have sufficient knowl-
edge of the Hygiene Systems and are confident with
the state work safety regulations, accident preventing
regulations, lines and generally acknowledged techni-
cal regulations such as DIN-norms and VDE-provi-
sions. For your safety, this cleaning unit has been
manufactured according to all relevant regulations
valid in the EU and therefore it has been supplied with
the CE-marking. For further information, please refer
to the service department.

9.4. Rinsing the chemical supply/injector system

The chemist supply must always be
rinsed thoroughly after use.
Remains of detergents or disinfectants can clog the
injector so it needs to be rinsed or replaced.
The following procedure will clean the chemistry sup-
ply for detergents and/or remains of disinfectants.
1. Remove User Pack, if any.
2. Hold the rinsing bottle with clean water tightly
against the suction opening (with User Pack) or
against the hose (without User Pack). Alternati-
vely, you can place a User Pack with clean water
in the holder or – without User Pack – place the
hose in a bucket of clean water.
3. Activate the hose handle until clean water comes
out of the nozzle (approx. 30 seconds).
This procedure should be
followed both on the detergent
and the disinfectant side (if this is
installed).

9.5. Deliming

• The interval of the Deliming procedure depends
on the water hardness.
• Make sure the water to the unit is disconnected.
• Remove the Cover from the unit.
• Dismount the injector block. Dismount the air valve
and the non-return valve for air, inclusive of the air
fittings.
• Put the injector block in a deliming bath – make
sure the dosing valve (the knob) is over the sur-
face.
• Wait for 60 minutes.
• Rinse the block in clean water.
• Mount the air valve and the non-return valve on
the injector block and mount the injector block in
the unit.
• Connect water to the unit.
• Test the unit in Foam position make sure the vacu-
um is sufficient, it is recommended to be between
14,8 - 20,7 inHg / -0.05 - 0.07 MPa.
• Test that the unit can start and stop in both foam
and rinse position
• Reinstall the cover on the unit
The following deliming interwals must be observed to
prevent lime building up in the unit, that can discon-
tinue operation of the unit
°dH ppm Time between Deliming
0-5 18-90 12 months
5-10 90-180 6 to 12 months
10-15 180-270 3 to 6 months
15-20 270-360 3 to 6 months
>20 >360 1 to 3 months

9.6. Coupling

It is recommended to lubricate all coupling parts regu-
larly (approx. once a week) with waterproof grease
to prevent leaks and damage of packings. If the unit
is equipped with a spray gun the piston of the gun
should also be lubricated.
In leaking quick couplings the packings should be
replaced.

9.7. Internal cleaning of the unit

We recommend opening and cleaning the unit inside
min. once a week.
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