POTTERTON COMMERCIAL PRODUCTS DIVISION
SECTION 2
INSTALLATION, OPERATION & MAINTENANCE MANUAL
NXR 3
PAGE 5
GENERAL
This boiler is
NOT SUITABLE
for installation in a
normally occupied area (i.e. kitchen).
A
LIFETIME GUARANTEE
is available on this boiler
please refer to our standard terms and conditions for
details.
The Potterton NXR3 is a cast iron sectional boiler
available in outputs from 90kW (4-section model) to
290kW (9-section model). The heat transfer surfaces
of the NXR3 have been specially designed to
maximise the boiler efficiency and the large
combustion
chamber
capacity
ensures
environmentally sound combustion reducing CO and
NOx emissions. Specially designed and prewired
control panels allow full boiler control and flow and
return manifolds have facilities to fit sensor pockets for
boiler management systems.
The NXR3 is suitable for running at variable low
temperatures under direct compensated control.
The boiler has match tested package burners,
available for Natural Gas, LPG, 35 Second & 28
Second Oil. Dual Fuel options are also available.
The NXR3 is suitable for use on fully pumped open
vented systems or a sealed system with a maximum
design pressure of 6-bar (87 p.s.i.) and a minimum of
1-bar (14.5 p.s.i.).
The NXR3 boiler is of the overpressure type with 5-
pass reverse flame design. The first two passes are in
the combustion chamber with the other three in the
convection tubes where the turbulence to achieve
high heat transfer is generated by the extended
surface area achieving efficiencies of 93% (net), 84%
(gross).
The NXR3 is constructed with BS1452 Grade 220
cast iron heat exchanger, constructed in accordance
with EN303.1. The boiler package meets gas and oil
requirements of M&E36 and the burners EN676.
The waterway sections are joined by cast taper
nipples and secured with tie rods. The combustion
chamber joints are sealed by heat resistant cord.
The powder coated mild steel casings have a 50mm
fibre insulation in the casing plus a 50mm fibre wrap
around the castings, thus reducing fuel consumption
and emissions.
The NXR3 is supplied unassembled, assembly tools
are provided and a list of the tools is given in Section
4.
STANDARD SUPPLY
•
Unassembled cast iron sections (number
dependent on boiler output).
•
Smoke box, optimising baffles, flueway door,
combustion chamber door, burner adaptor plate,
flanged flow and return connections.
•
Boiler wrap round insulation
•
Insulated casing
•
Cleaning brush
•
Flow manifold complete with sensor pocket, ¾”
screw socket and plug
•
Eco control panel
CONTROLS
The NXR3 range is supplied as standard with an
integral control panel which is fitted with hours run
meters, flue thermometer, on/off, control and high/low
thermostats, limit thermostat, water thermostat, reset
button, high temperature warning light, mains on/off
light and fuse. Two volt free remote status contacts
and two hours run meters are included.
OPTIONAL EXTRAS
•
3 phase burners
•
Additional volt free contacts
•
Fully closing air dampers on burner
•
Sequence Control Options
SHIPPING - PACKAGING
The boiler package is delivered unassembled on two
pallets with the burner separately either in a carton or
on a pallet.
Pallet 1
Unassembled sections and door.
Pallet 2
Casing pack, boiler accessories, boiler fittings, tie
rods, baffles, flow and return turrets, control panel.
See Section 7 for breakdown of contents.
It is recommended that Potterton Commercial
Division’s trained engineers should carry out erection
and commissioning, as this will make valid the
LIFETIME GUARANTEE. See back page of this
manual for service office addresses
.