Airflow 90001299, User Manual

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User Manual
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PART I – GENERAL DEFINITIONS
1. General Information
1.1. Introduction
Lately, most of the people 's life is spent in doors ( at home, office, etc ) and indoor air quality has become a
very important topic . To help reducing the indoor air pollution , heat recovery units have been designed.
Mechanical Ventilation with Heat Recovery (MVHR) ensure s that the stale air is ex tracted from the indoor
environment , heat is recovered within the plate heat exchanger, and fresh filtered air is supplied
indoors being warmed-up within the heat recovery core at a requested temperature . Many design building
projects include h eat r ecovery u nits being requested by the user s . The biggest challenge in using
the se unit s is the controller. The main difference between basic heating-cooling systems (fan-coil, duct type
fan, duct type indoor units, etc.) and ventilation units is that the ventilation units have two fans to control
( supply and extract fans) . Both fans must be controlled separately in various operating conditions.
For instance , in some cases it may be requested to keep the ventilated environment to a positive
pressure (supply only) or a negative pressure (extraction only). In this case, it is required to set both
fans at different speeds or one fan on and the other fan off. Also , it is possible to adjust the
ventilation amount automatically depending on the amount of CO
2
or moisture in these units, which
leads to sav ing energy, thanks to the on - demand ventilation. In addition , according to the latest building
regulations, the summer by-pass function is a requirement ( the fresh air is bypassing the plate
heat exchanger, being supplied indoors directly) . Thanks to the HRU Controller developed by our
company, all functions and safety requirements expected from a h eat r ecovery u nit can be met.
Different working scenarios have been created for customer 's demands and control of different
ancillaries to be used with the units.