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Variable air volume controllers
Offices
Office buildings generally require good
ventilation during the day as well as heat
and cooling recovery and reconditioning of
supply air depending on external condi-
tions. Ventilation systems with demand
control should be considered for offices
where staffing levels vary. As a rule, offices
develop an excess of heat produced by
people, lighting, solar radiation, computer
equipment, etc. In many cases there is a
need to cool the air and prevent uncom-
fortable high temperatures. In larger build-
ings that accumulate heat energy easily,
you should consider employing night cool-
ing. If the office is in a city environment, a
higher filtration class should be used. In an
office environment, there is also consider-
able need to reduce the noise generated by
the ventilation system.
Schools and nurseries
A school environment means a lot of peo-
ple present at certain times of the day, i.e.
generally there are relatively large varia-
tions. This means that it should be possible
to use demand control for the ventilation
system. Normally, with heat and/or cool
recovery is warranted. There will be short
periods during the year when heating may
be required. However if there is effective
sunscreening, then air reconditioning is
rarely required. High demand for low noise
levels. At day nurseries, activities such as
cooking that create odours are common,
so there is often a need for supply air and
extract air to be kept separate. There must
be heat recovery in the form of a plate heat
exchanger, for example.
Shops
As a rule, the number of people in a shop
changes constantly throughout the day,
making a control-on-demand ventilation
system the sensible option. Recirculating air
in combination with carbon dioxide control
(CO
2
) and heat recovery can be one opti-
mised solution for these types of premises.
When there are few people present, CO
2
levels will be low and an increased amount
of return air can be mixed into the system.
As the number of people present increases,
the amount of return air is reduced and
replaced with fresh outdoor air. If heating
is required at night-time, the premises are
warmed up using 100% recirculating air.
