Effi Ciency Up To 98 - PEERLESS Combi 160 Installation, Operation & Maintenance Manual

4 - FUNCTION OVERVIEW
4.3 - Effi ciency up
to 98%
When the outdoor reset is activated
(see section 12.10) and an outside
sensor is connected, this boiler
is designed to always work at
the maximum effi ciency. It will
automatically change the supply
temperature in relation with the
outdoor temperature (Outdoor reset).
The graph in fi gure 3 shows an
example on how it can work.
This graph is an example where is
represented an installation where
the supply and return temperatures
are 139°F and 115°F respectively ,
and the outside temperature is 23°F.
The outdoor reset drives the boiler,
to progressively reduce the supply
temperature and thereby optimize
the effi ciency. It changes from 87%
when outside is -10°F, to 94.8% when
outside is 23°F and up to 98% when
the outside temperature rises up to
67°F.
Figure 3 - Outdoor reset control to optimize the effi ciency
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