gledhill StainlessLite D120 Design, Installation & Servicing Instructions page 15

d) It is preferable for the discharge to be visible at both the tundish and the final point
of discharge but where this is not possible or practically difficult there should be
clear visibility at one or other of these locations. Examples of acceptable discharge
arrangements are:
1. Ideally below the fixed grating and above the water seal in a trapped gulley.
2. Downward discharges at a low level; i.e. up to 100mm above external surfaces
such as car parks, hard standings, grassed areas etc are acceptable providing that
where children play or otherwise come into contact with discharges, a wire cage
or similar guard is positioned to prevent contact whilst maintaining visibility.
3. Discharges at a high level; e.g. into metal hopper and metal down pipe with the
end of the discharge pipe clearly visible (tundish visible or not) or onto a roof
capable of withstanding high temperature discharges of water and 3m from
any plastic guttering systems that would collect such discharges.
4. Where a single pipe serves a number of discharges, such as in blocks of flats,
the number served should be limited to not more than 6 systems so that any
installation can be traced reasonably easily. The single common discharge pipe
should be at least one pipe size larger than the largest individual discharge pipe
to be connected. If unvented hot water storage systems are installed where
discharges form safety devices may not be apparent i.e. in dwellings occupied by
blind, infirm or disabled people, consideration should be given to the installation
of an electronically operated device to warn when discharge takes place.
Secondary
Return Circuit
P&T Relief Valve
Pump Non Return
Valve
Immersion Heater
Stop
Tap
Boiler
Flow
Kitchen
Boiler
Cold
Return
Tap
Schematic Diagram
Hot Outlet
To Drain
2 Port Valve
INSTALLATION
Tundish
Expansion Vessel(s)
Balanced
Cold
Outlets
ERV
NRV
PRV
Combination
Valve
Page 15
Safety
The safety devices supplied or fitted on an
Stainless Lite are selected for their suitability for
the temperatures and pressures involved. They
must not be changed, removed or by-passed
and it is essential that only genuine replacement
parts supplied or approved by Gledhill Building
Products Limited are used. All parts are available
to approved installers from Gledhill Building
Products Limited, Sycamore Estate, Squires Gate,
Blackpool (Telephone 01253 474402).
Line Strainer
This is integral within the combination inlet
group to reduce the likelihood of contaminants
fouling the valve seat. Following installation this
line strainer must be cleaned and replaced. This
needs to be carried out on a regular basis. as part
of the annual maintenance/service check.
Tundish
This is to allow the discharge from any Relief
Valve to be seen. It must be fitted away from
any electrical devices. See page 14 for discharge
pipework details.
Combination Inlet Group
Combines elements 1, 2 and 3 below.
1. Pressure Reducing Valve - This must be fixed
near the cylinder. The cold water supply to
any mixer taps/showers must be taken from
the cold water tapping of this valve to ensure
balanced hot and cold pressures. This valve
is factory set to ensure the correct operating
pressure for the Stainless Lite.
2. Non Return Valve - This is integral with the
pressure reducing valve to prevent backflow of
hot water towards cold water draw off points.
3. Cold Water Expansion Relief Valve - This safety
device is preset at the factory and will relieve
excess cold water pressure resulting from a
fault condition.
2 expansion cylinders on 400 litre Models
All 400 litre models are supplied with two 24
litre expansion cylinders. These can be coupled
together and fitted to the expansion cylinder
tapping on the combination inlet valve, or by
some other means on the cold/hot water inlet
pipework. There must be no valve on the pipe
work between the expansion cylinders and the
unvented cylinder which could prevent the
expansion of the water contained in the unvented
cylinder reaching the expansion cylinders.
INSTALLATION