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Operation and Maintenance
Envistar Flex
DSEF191101.05.EN
Continuous product development may give rise to specification changes without notice.
Function
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. Simulate reduced required output by temporarily lowering the temperature
setting (setpoint), so that all the electric output steps (contactors) switch out.
2. Then sharply increase the setpoint setting and check that the electric output
steps switch in.
3. Restore the temperature setting.
4. Stop the air handling unit (NB: Do not break the circuit with the safety
switch). All the electric output steps should switch out (i.e. the contactors in
the OFF position). Stopping the unit may be delayed approx. 2–5 minutes to
allow the fans to cool the heat energy stored in the air heater.
The electric heater is equipped with dual temperature limiters. The one that
resets itself automatically should be set to 70°C.
The overheat protection with manual reset interrupts operation when the heater
reaches approx. 120°C and is located on the cover panel on the side of the
heater.
Determine the cause of overheating and take corrective action
before you reset the protection device.
Please note that the risk of overheating increases as the air flow through the unit
decreases. The air speed should not be lower than 1.5 m/s.