G-8
A-070336_EN • Rev. A
Nesta 120 - 160 - 200 - 250
General Description
This floor-standing series of Nesta boilers consists
of compact, low-emission condensing appliances
with a pre-mix burner and a stainless steel heat
exchanger. The housing of the boiler is made of
aluminium.
The fully radial burner ensures a high modulation ra-
tio, combustion stability and very low NOx emissions.
The stainless steel heat exchanger offers a high
water capacity and a large heat exchange surface
to optimise energy and heating efficiency.
This series is designed for heating systems and
can be used for indirect Domestic Hot Water pro-
duction (provided that the system contains an op-
tional external tank).
Nesta boilers are able to control 3 heating circuits
with mixing functions, through 3 optional extension
modules . Each extension module requires a power
supply and a bus connection. Refer to
for more information.
These appliances
are not
provided with a built-
in circulating pump. Therefore, the hydraulic sys-
tem must be equipped with at least one pump for
standard system flow operation.
The Nesta boilers can be connected in a cascade
configuration, which means that the boilers are
connected to the same water circuit and electronic
controller, with one boiler operating as the master,
and the others as “slaves”). Refer to
for more infor-
mation on cascade system possibilities.
Frost Protection
The Nesta boilers have a built-in an ti-frost protec-
tion. The pump and the burner are started as re-
quired when the return water temperature drops
below 5°C (as measured by the boiler internal sen-
sor installed on the return circuit). The pump and/
or burner will turn off when the re turn temperature
reaches the required setpoint. The anti-frost pro-
tection function only protects the boiler, not the en-
tire system.
P
roduct
d
escrIPtIon
Safety Devices
The Nesta boilers are equipped with a series of
sensors and switches that provide safety for your
appliance and heating system, such as:
î
Water circuit temperature sensors (supply, re-
turn, system, etc.)
î
Burner plate temperature limit switch
î
Gas pressure switch
î
Water pressure sensor
î
Flue temperature sensor
î
Condensate level switch
î
Alarm contacts
The Nesta boilers
are not
provided with the follow-
ing mandatory safety equipment that the installer
must place in the system:
î
Expansion tank, suitable for the system size,
î
Safety group, composed of a safety valve (pres-
sure rating adapted to the system), an automat-
ic air relief valve and a manometer,
î
Air relief valve(s), at the high point(s) of the sys-
tem.
Optional equipment
Some optional equipment can be used with the
Nesta boilers. Please contact your AIC Europe rep-
resentative for more information and a list of avail-
able equipment.
To lengthen the life of your boiler and heating sys-
tem, in addition to the recommended water char-
ments to Prevent Scaling and Corrosion” on
the following equipment can be in-
stalled in the heating circuit:
î
Water filter
î
Dirt separator
î
Low loss header
î
Plate heat exchanger
î
Air separator
See
“Requirements for the Hydraulic Connec-
for more information on this
equipment.