Lifebreath 1500E-ECM, Руководство по установке

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TALE
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IR
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ETURN
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RESH
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UPPLY
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YSTEM
Stale Air Return System
Many commercial activities produce air contaminants in the form of dusts, fumes,
mists, vapors and gases. Contaminants should be controlled at the source, so that
they are not dispersed through the building nor allowed to increase to toxic
concentration levels. The heat recovery ventilator allows for economical operation
of the HVAC system while effectively removing contaminants from the space. In
designing the exhaust portion of the system, the exhaust grilles are placed to
remove the contaminants while not allowing them to enter the breathing zone of
the occupants.
The stale air return system is used to draw air from the points in the building where the worst air quality problems occur.
Balancing dampers and/or adjustable grilles are recommended on all return air lines which are used during installation to
help balance the "draw" from different areas of the building. Note that the installation schematics show balancing
dampers and/or adjustable grilles on all return air lines coming back to the unit.
For contaminants that are lighter than air, grilles should be located high on the wall. If contaminants are heavier than air,
a lower placement of the grilles will be required. Information on a contaminants specific gravity and toxicity should be
available from the chemical data sheets.
Alternately, the stale air may be drawn directly from the return air duct. When this system is used the air handler's blower
will need to operate constantly when ventilation is required. The exhaust takeoff connection must be at least 3 ft (1 m)
from a directly connected HRV supply duct if both are connected to the same duct run. Note and compensate for the
static pressure of the air handlers return system if the static pressure of the return in the air handler exceeds 0.1 to 0.15
in. w.g.
A damper located just prior to the HRV is required to balance the stale air exhausted with the fresh air supply entering
the building.
Return air suction points should be located at the opposite side of the room to the fresh air inlet. The inlets may be in the
ceiling or high on the walls and fitted with inlet grilles.
Fresh Air Supply System
The fresh air supply ductwork from the HRV may be directly connected to the return
air duct of the forced air system. When directly connected it is recommended that
the air handler blower be in constant operation to move the fresh air about the
building. Also, it is advisable to include a short length of fabric flex duct or other
non-metallic connector in this hard ducted line in order to keep the HRV acoustically
isolated and separately grounded (electrically) from the air handler. This will avoid a
possible shock hazard to service people if a short to ground develops in one of the
devices. It may be necessary to install a separate fresh air supply ductwork system
if the heating is other than forced air.
When installing an HRV, the designer and installer should be aware of local codes that may require smoke detectors
and/or firestats in the HVAC or HRV ductwork. Because an HRV is designed to bring fresh air into the building, structures
may require a supply voltage interrupt when smoke or flame sensors are triggered, or central fire alarm system is
activated.
The use of balancing dampers or adjustable grilles as supply air diffusers and air exhaust grilles are recommended.
TECHGRILLES™ are round, efficient, sound absorbing devices available in 4", 5", 6" and 8" (100, 125, 150 and 200mm).
Supply air grilles may be ceiling or high wall mounted. Avoid locating incoming fresh air grilles that could cause a direct
draft on the occupants as the incoming air may be below room temperature. A reheat duct heater can be installed to
improve occupant comfort.