gledhill Torrent GreenHeat TGH140-OV Design, Installation & Servicing Instructions page 19

Max.
height
10m
2 Pump System With Dipped Boiler Flow and Return Pipe
Must comply
with boiler
manufacturer
instructions
2 Pump System
Min. 250mm
Min. 250mm
Page 19
INSTALLATION
Open vented heating systems
The open vented primary system is fi lled via the
feed and expansion (F&E) tank fi tted with the
Torrent OV model and therefore it is important that
the F&E tank is positioned at least 250mm above
the highest point in the system. Please check
the F&E tank is big enough for the whole system
expansion. Also ensure that the height of the
F&E tank is suffi cient to meet the manufacturer's
requirements for the minimum head required for
the boiler and the system pump(s).
The Torrent OV models can be installed using
both 'Y' Plan and 'S' Plan heating system controls.
These models can also be installed without either
3-port or 2-port valves using a separate central
heating pump as shown in diagrams on this
page. In this case no bypass valve is required
unless TRV's are used on all radiators.
If the fl ow and return pipes between the boiler
and the Torrent OV thermal store are dipped
as illustrated in the schematic shown opposite,
then the boiler selected must be suitable for a
sealed heating system i.e. it must be fi tted with
an overheat thermostat. Automatic air vents
should be fi tted at appropriate places to vent
the system and a pressure relief valve should
also be fi tted close to the boiler.
Any boiler can be used with the Torrent OV and
the Torrent SOL provided the fl ow pipe from the
boiler to the Torrent is continuously rising. The
fl ow pipe between the boiler and the Torrent
thermal store is part of the open vent and
therefore it must not be fi tted with any isolating
valve, non-return valve or any other component
which can obstruct the fl ow.
The minimum size of flow and return pipe
between the boiler and the Torrent should be
22mm copper or equivalent. In any case it should
be sized to suit the installed boiler capacity,
available pump head and the circuit resistance.
The water level must be set correctly by adjusting
the ball valve in the F&E tank. The overflow/
warning pipe, should be no less than the 20mm
internal diameter and have a continuous fall.
The overfl ow/warning pipe should be fi tted to
discharge clear of the building and be sited so
that any overfl ow can be easily observed. The
warning pipe should be installed in either high
temperature uPVC or copper and should not
have any other connections to it.
If the boiler does not incorporate an overheat
thermostat, then one should be fi tted to the store.
TORRENT GREENHEAT OV