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Operation and maintenance
Envistar Compact
DSEC181201.00.EN
Continuous product development may give rise to specification changes without notice.
7.5 Air heater electric (code ECET-EV)
Air heater electric (code ECET-EV)
The heating coil consists of “unsheathed” electric heating rods. A substantial
accumulation of dust or other impurities on the heating rods will cause them to
overheat. This could shorten their service life. This might also entail an odour of
burnt dust and, in the worse case, the risk of fire. Overheated electric heating
rods may become deformed or loosen from their suspension fasteners and heat
the air unevenly.
Inspection
Check that the electric heating rods are correctly positioned and that they are
not deformed in any way.
Cleaning
Vacuum and/or wipe all surfaces with a cloth.
Function
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. Shut down the unit via the service switch in the control equipment, safety
switch in the 0 position.
NB:
The safety switch is not designed for starting/stopping the unit. Always
use the service switch in the control equipment to start and shut down
the unit.
4. 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 re-
sets 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 be-
fore 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.
Summary of Contents for Envistar Compact Series
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