system
air
41
3.5 Heat recovery units
3.5.1
Plate heat exchanger
Caution
See also section 3.1 General instructions.
See the values in the selection program data and on the nameplate.
Commissioning
•
Prior to starting the section up, check the tightness of the threaded joints and tighten them if required. Also check
the correct installation and connection of the control dampers with the damper electric motor drive, as well as the
damper operation.
•
Make sure to allow for unobstructed removal of the water droplet eliminator from the air handling unit casing.
•
Make sure to install an adequately-sized siphon in the condensate collection and draining pan discharge pipe. The
instructions for the construction, installation and connection of siphons are provided in Section 2.3.5 Connection of
siphon.
Maintenance
Regularly clean the plate heat exchanger. Fouling of the insert increases the pressure drop and decreases the
efficiency.
A simple way to check for plate heat exchanger fouling is to remove the covers on the service side and inspect the
cleanliness of the insert front surfaces, and, with the aid of a torch lamp, also the cleanliness of the air channels
through the insert.
If the insert contamination consists of dry dust, the insert can be cleaned without disassembly through the service
openings:
•
With compressed air (a maximum of 10 bar of pressure); in this operation, the use of personal protective equipment
is obligatory.
•
If the insert contamination consists of greasy or sticky debris, slide out the insert from the heat exchanger section
casing and clean it with a jet of hot water (temperature up to 90 °C, a maximum pressure of 6 bar) with an
appropriate cleaning agent added.
•
The contamination may also be removed by means of soaking in warm water with a detergent added.
Disassemble the insert from the casing:
•
Rremove the partition profiles on the service side by undoing the mounting screws,
•
remove the rubber gasket,
•
undo the top guide profile mounting screws, while only loosening the side guiding profiles, and then remove the
top guide profile,
• slide out the insert from the section casing,
• replace the cleaned inserts in the section in the reverse order of the mentioned steps.
Caution
Since the insert filler material is made of a very thin aluminium foil, be careful not to damage the front
surfaces of the insert when disassembling.
With any maintenance or inspection intervention, also clean the condensate discharge at the bottom of
the pan and top up the water in the siphon.
