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WARNING!
The high pressure water jet may compress the dirt and impurities into the plate gaps
and block the flow passages.
5.2.4 Analysis after cleaning
Analyse if pollution could be avoided by:
¬ Installing strainers
¬ Decreasing temperatures (installing desuperheater)
¬ Increasing system pressure
¬ Refreshing the medium more frequently, or at shorter intervals
¬ Adjusting the concentration of the medium
¬ Increasing the flow between the plates
¬ Changing the capacity control to a system with constant flow.
5.3 Openable model
The plate pack in openable heat exchangers can be taken out of the shell and cleaned
using a high pressure cleaner. When removing it, follow these instructions in order to
avoid damaging the plate pack and flow directors.
WARNING!
Never apply pressure to the plate pack outside the shell. The plate pack’s support
structures are not designed to withstand forces resulting from pressure exerted on it,
which may cause an accident.
5.3.1 Preparations
It is recommended that the unit should be moved to a location that is spacious enough
to carry out any required service or maintenance. Drain the exchanger on both the
plate and shell sides and open all the pipe connections before moving the unit. If the
exchanger cannot be moved, only open the connection pipes on the plate side and
ensure that there is enough room in front of it to remove the plate pack (the minimum
space needed is the entire length of the exchanger).
When removing the plate pack from the shell, measure the pack length from the gasket
surface to the end of the pack, and the shell length from the gasket surface to the end
plate. The plate pack must be supported by the end plate when installed in the shell.
If the plate pack is replaced, measure the shell to ensure the fit of the new plate pack.
See section 9.2.
5.3.2 Opening the exchanger and removing the plate pack
Option 1 (recommended)
Move the unit to a more specious area and turn it so that the end plate connections are
facing upwards (plate pack vertical).
Remove some of the bolts from the cover plate and install guide bars (4-6) in the bolt
