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Operation and Maintenance Instructions
Envistar Top 04-21
DSET.181201.00.EN
Continuous product development may give rise to specification changes without notice.
6.7 Air cooler water (code ATET-VK)
Air cooler water
The cooling coil consists of a number of copper tubes with aluminium fins
pressed onto them. The coil will have impaired capacity if dust forms a coating
on the coil surfaces.
Not only does this impair the heat transfer capacity of the coil, it also increases
the pressure drop on the air side.
Even if the ventilation system is fitted with high quality filters, as time passes
dust deposits will form on the front edges of the coil fins (at the inlet side). A
drip tray with drain is located under the cooling coil for collecting and removing
evaporation water.
Inspection
Check:
1. The coil fins to detect possible mechanical deformity
2. That the water coil is not leaking
3. That cooling energy is uniformly distributed across the coil surfaces (in op-
eration)
4. The drip tray and drain with water trap (clean if necessary)
5. That the water trap (without non-return valve) is filled with water.
Cleaning
If the fins on the batteries are dirty, clean them by vacuuming from the inlet side,
or carefully blow them clean with compressed air from the outlet side. In the
event of stubborn dirt, use a mild, alkaline detergent.
For more information, refer to
.
Bleeding
Bleed the cooling coil and the pipe connections if needed. Bleeder screws are
on top of the coil or on the tube connections.
Function
Check that the coil is emitting cooling energy. This can be done by temporarily
lowering the temperature setting (setpoint). Note that cooling is blocked when
the outdoor temperature drops below the set value for cooling start. (For control
equipment (code MX) Login 2000 - Main Menu/Unit/Temperature
Control/Cooling/Block at outdoor temp).
