Page 34
Operation and Maintenance
Envistar Flex
DSEF191101.05.EN
Continuous product development may give rise to specification changes without notice.
Inspection
DANGER!
Risk of serious personal injury and/or damage to air handling
unit.
Read and understand the entire chapter "1.5 General safety
messages" before working on, servicing, or inspecting the air
handling unit.
1. Shut down the unit via the service switch in the control equipment, safety
switch in the 0 position.
2. Wait until the fans have stopped, then open the inspection hatch.
3. Inspect the fins for fouling.
4. Perform a visual inspection of the dampers and damper motors on frost
protection equipment.
5. Check that the bypass damper is tightly shut when defrosting is not taking
place.
6. Check the waste oulet and water trap function. A water trap without a non-
return value should be filled with water.
Cleaning
DANGER!
Risk of serious personal injury and/or damage to air handling
unit.
Read and understand the entire chapter "1.5 General safety
messages" before working on, servicing, or inspecting the air
handling unit.
The plate heat exchanger is designed to prevent dirt and deposits from coming
into contact with the heat transfer surfaces. Most of the particles in the air
simply pass through the plate heat exchanger. The main risk for fouling of the
counter-flow exchanger comes from slow-moving substances that condense on
the surfaces, and also from fibres from tumble dryers, for instance.
The recommended way to clean the plate heat exchanger is by vacuuming,
compressed air blowing, and flushing with hot water (if necessary, add some
mild detergent that is not corrosive to aluminium). Also clean the drip tray,
bottom plate, drain and water trap.
NB!
High pressure flushing must not be directed at the fins. Be
careful in order to ensure that the fins do not become deformed
or break.
At operating temperatures below 0 °C, the plate heat exchanger must be dry
before commissioning.