Optional Filter And Filter Access; Fresh Air Controller; Optional Water Flow Control Valves - Carrier 42EM ATMOSPHERA Manual De Instalación

4.4 - optional filter and filter access

4.4.1 - Description
The Carrier Atmosphera is fitted with a 85% gravimetric
filter (G3), according to standard EN 779. Medium fire
rating M1, metal wire frame.
Different filter access options are available to suit different
site requirements:
• Unit with non-ducted return air: Access is from the
rear of the unit.
• Unit with ducted return air: Access is from below.
4.4.2 - Air filter replacement
Air filters should be changed regularly. Filter life depends on
the rate at which the filter becomes clogged, which depends
upon the cleanliness of the working environment.
If clogged filters are not changed they can increase the air
pressure drop, trapped dust particles may be given off and
entrained in the air supply, and the general performance of
the Atmosphera may be degraded (as the air flow reduces).
NOTE: When installing an Atmosphera in a ceiling void,
check that no T-bars will obstruct filter access and removal.

4.5 - Fresh air controller

4.5.1 - Fresh air controller with constant air volume
The 42EM Atmosphera can be fitted with a constant fresh
air flow controller, fixed at 8.5 l/s (30 m
from 17 l/s (60 m /h) to 44 l/s (160 m
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the introduction of fresh air and of the air change rate.
Controllers with adjustable fresh air flow:
The diameter of the spigot housing the fresh air flow
controller is 125 mm.
The fresh air controller may be modified on site by relocating
or removing two plastic restrictors in order to change the
maximum constant fresh air flow of 17 1/s (60 m
(160 m /h). A label on the 42EM shows how to adjust the
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two plastic restrictors (Fig. 11).
Modification procedure
• Disconnect the fresh air duct from the spigot on the
Atmosphera.
• Remove or reposition the two plastic restrictors,
following the fresh air flow controller.
• Reconnect the fresh air duct to the spigot.
IMPORTANT: If the Atmosphera is fitted with a return
air temperature sensor, the constant fresh air flow rate
must not exceed 50% of the supply air flow delivered by
the unit at minimum speed.
NOTE: To operate correctly, the 8.5 l/s (30 m
constant fresh air flow controller requires a differential
pressure in the range of 50 Pa to 200 Pa. The controller with
adjustable fresh air flow from 17 l/s (60 m
(160 m /h) requires a differential pressure in the range of
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70 to 200 Pa.
16
/h) or adjustable
3
/h) to allow contol of
3
/h) to 44 1/s
3
/h) the
3
/h) to 44 l/s
3
4.5.2 - Fresh air controller with variable air volume
The 42EM Atmosphera can be equipped with an optional
variable fresh air flow controller from 0 to 55 l/s (0 to 200
m /h).
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This is connected to the numeric Carrier controller and
can regulate the fresh air intake in two ways:
• either using a fixed rate set by the installer that can be
reconfigured as required
• or based on the CO
to a CO sensor via the Carrier numeric controller
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(the CO sensor is located opposite the fresh air inlet).
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NOTE: With the variable fresh air flow controller the
upstream pressure in the fresh air duct must be 180 Pa.

4.6 - optional water flow control valves

These valves are two-way or four-way type, with a body
designed to withstand a 16 bar operating pressure.
4.6.1 - Electrothermal actuator (on/off)
The actuator is a 230 V a.c. on/off type.
To enable the installation to be filled with water, the
water circuits to be equalised and the units to be purged,
the actuators must be connected to the power supply to
open the valves via a command from the wall thermostats
or from the BMS.
4.6.2 - Actuator replacement procedure
The actuators on both the chilled water and the hot water
valves may be replaced if either develops a fault.
• Disconnect the power supply to the unit before carrying
out any work on a unit.
• Disconnect the actuator power supply cable.
- 230 V on/off type actuator used with the Carrier
numeric controller: Disconnect the actuator
power supply cable fitted with a quick connector.
- 230 V on/off actuator used with an electronic
thermostat: Remove the plastic protection cover
held in place with two screws. Disconnect the
actuator power supply cable connected to the
quick connector. This can be done by pressing
down the spring tongue using a screwdriver and
pulling out the wire from the appropriate terminal.
• Uncouple the faulty actuator. Refitting is by the reversal
of the procedure described above.
WARNING: Ensure that the actuator is firmly screwed to
the valve body (maximum torque 15 N·m).
level; in this case it is connected
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