gledhill Torrent Stainless OV, Instruction Manual

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INSTALLATION INSTALLATION
INSTALLATION TORRENT STAINLESS OV
Boiler Size
The minimum total boiler power required is the
sum of the power required for space heating
which should be calculated in accordance with
BS EN 12831 and/or the CIBSE guide and the
power required for producing hot water which
can be read from the table to the left.
The coil performance figures are based on a
boiler flow temperature of 82°C and flow rate
of 0.25 litres per second. The boiler needs to be
able to modulate down to the 7°C temperature
difference setting to maximise efficiency.
Please see page 18 for pipework configuration
where Torrent Stainless SP SOL is selected and
both coils are to be used with a boiler.
Expansion Vessel For Sealed Heating System
The table opposite can be used for sizing the
heating system expansion vessel. The water
content of the Torrent Stainless primary heat
exchanger is listed in specification tables on
pages 4 and 5 and a figure of 4.5 l/kW of installed
radiator capacity can be used for a preliminary
assessment of the water content of the heating
system.
The expansion vessel requirements shown in
the table are based on a maximum boiler flow
temperature of 93°C. The expansion vessel
must be suitable to accommodate the change
in volume of water in the heating system when
heated from 10°C to 100°C, with a maximum
operating temperature of 99°C.
Feed And Expansion Tank For Open Vented
Heating System
The table opposite shows the recommended
size and number of F & E tanks required for an
open vented hot water only system, which can
be supplied as an optional extra.
Expansion for the open vented heating systems
connected to the store must be added to this
figure. So, as a preliminary assessment of the
water content of the attached open vented
systems, a figure of 4.5 l/kW of radiator output
can be used. For example, 20 kW radiator output
would have a system volume of 90 litres, and
potential expansion of this would be 3.6 litres,
and 10 kW would be 45 litres total volume and
1.8 litres for expansion.
Please refer to page 19 for further information
regarding F&E tanks when using solid fuel input.
Allowance for domestic hot water for sizing the boiler
Torrent Stainless model
Allowance for domestic hot water heating (kW)
Full divert mode Flow share mode
150 0 2
180 0 3
210 0 4
250 0 5
350 0 7
Open vented heating systems
The open vented primary system is filled via the
feed and expansion (F&E) tank fitted with the
Torrent Stainless 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 sufficient to meet the
manufacturer’s requirements for the minimum
head required for the boiler and the system
pump(s).
The Torrent Stainless 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 flow and return pipes between the boiler
and the Torrent Stainless 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
fitted with an overheat thermostat. Automatic
air vents should be fitted at appropriate places
to vent the system and a pressure relief valve
should also be fitted close to the boiler.
Any boiler can be used with the Torrent Stainless
OV and the Torrent Stainless SOL provided the
flow pipe from the boiler to the Torrent Stainless
is continuously rising. The flow pipe between
the boiler and the Torrent Stainless thermal
store is part of the open vent and therefore it
must not be fitted with any isolating valve, non-
return valve or any other component which can
obstruct the flow.
The minimum size of flow and return pipe
between the boiler and the Torrent Stainless
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 overflow/warning pipe should be fitted to
discharge clear of the building and be sited so
that any overflow 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 fitted to the store.
Sealed Heating System Expansion Vessel Requirements
Safety valve setting 3.0
Vessel charge
pressure (bar)
0.5 1.0 1.5
Initial system charge
pressure (bar)
0.5 1.0 1.5 2.0 1.0 1.5 2.0 1.5 2.0
Total System
Volume (litres)
Expansion Vessel Volume (litres)
25 2.1 3.5 6.5 13.7 2.7 4.7 10.3 3.9 8.3
50 4.2 7.0 12.9 27.5 5.4 9.5 20.6 7.8 16.5
75 6.3 10.5 19.4 41.3 8.2 14.2 30.9 11.7 24.8
100 8.4 14.0 25.9 55.1 10.9 19.0 41.2 15.6 33.1
125 10.4 17.5 32.4 68.3 13.6 23.7 51.5 19.5 41.3
150 12.5 21.0 38.8 82.6 16.3 28.5 61.8 23.4 49.6
Thermal Store
Minimum Number of Feed and Expansion Tanks
(16 litre model inc. 10 litre expansion)
TST150, TST180, TST210 1
TST250, TST350 2
Expansion of all connected open vented systems must be added to the store
expansion when choosing the size of the feed and expansion tank.
The weight of each tank when full is 27kg (not including pipework and valves).
2 Pump System
Max.
height
10m
Min. 250mm
2 Pump System With Dipped Boiler Flow and Return Pipe
Must comply
with boiler
manufacturer
instructions
Min. 250mm
Coil Performance
Nominal volume
litres 150 180 210 250 350
(SP SOL) Primary coil only
Coil power at 7°C temp.
difference
kW 3 4 6 6 7
Average power kW 9 13 15 16 18
Coil power at 47°C temp.
difference
kW 23 26 33 32 36
Volume of water heated litres 84 102 130 144 230
Recovery time min 22 18 22 20 28
(SP SOL) Combined coils coil
Coil power at 7°C temp.
difference
[kW] 4 4 6 4 3
Average power [kW] 12 16 18 16 15
Coil power at 47°C temp.
difference
[kW] 25 36 39 36 41
Volume of water heated litres 150 180 210 250 350
Recovery time [min] 25 28 30 34 42
coil cofiguration series parallel parallel parallel parallel