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0020004886A
4.1 Installation requirements
4.1.1 Siting
IMPORTANT. With regards to the Manual Handling Operations,
1992 Regulations, the following lift operation exceeds the
recommended weight for a one man lift.
Locate the Glow-worm cylinder in the building in the most
convenient position ensuring that:
1. The discharge pipe from the tundish can be installed with a
minimum fall of 1:200 and must be terminated in a safe and
visible position (see section 4.1.4 Discharge pipework).
2. The base chosen for the unit is level and capable of supporting
the weight of the cylinder when full (see section 8: Technical
Data).
3. The installation site is frost-free. If necessary provide a frost
protection thermostat.
4. Access is available for user operation of the DHW temperature
control under the front panel.
5. Suitable clearances exist to allow installation, checking and
repressurising of the expansion vessel.
6. The installation site chosen does not result in excessive
”dead leg” distances, particularly to the point of most frequent
use.
7. A suitable cold mains water supply pipe can be provided to
the Glow-worm cylinder direct from the main water stop valve
of the building.
This product has been assessed and found to comply with the
requirements of the Building Regulations for unvented hot
water storage systems and must not be altered or modified in
any way.
The installation must be carried out by a competent person and
be in accordance with the relevant requirements of the Local
Authority, Building Regulations, Building Regulations (Scotland),
Building Regulations (Northern Ireland), and the bye-laws of
the local Water Undertaking. The installation is subject to
Building Regulation approval, notify the Local Authority of
intention to install. In the event of parts replacement, use only
genuine spare parts supplied by Glow-worm.
3.1 Secondary System
The Glow-worm cylinder is provided with all necessary safety
and control devices for unvented DHW operation.
These are as follows:
A A prefitted temperature and pressure relief valve
(95°C, 7 bar).
B A Thermal cut set at 90°C which when wired to the
2 port valve will isolate the heat source in the event
of failure of the cylinder thermostat.
C A cylinder thermostat (20°C - 60°C)
D Expansion relief valve (6.0 bar) incorporating a non
return valve.
E Pressure limiting valve (3.5 bar) incorporating a line
strainer.
Check that the cylinder has been supplied with the
following:
Packed inside cylinder carton
• Water control pack (pressure reducing valve,
expansion relief valve; connections for: balanced cold
water, secondary return, expansion vessel)
• Motorised 2 port valve
• Tundish
• Cylinder drain valve,
• Installation and user instructions.
Expansion vessel:
• 12 litre for Glow-worm cylinder 115/150
• 18 litre for Glow-worm cylinder 175/200
• 25 litre for Glow-worm cylinder 250/300
Accessories: Mounting bracket No. 370 214
Prior to installation, ensure that the Glow-worm cylinder is
stored upright in dry conditions. The Glow-worm cylinder must
be kept
upright during transportation.
Please also refer to “General Requirements“ in the
installation instructions supplied with the boiler.
3.2 Secondary Return
A scondary return connection is provided in the water
control pack.
Connect onto the 1/2“ pipe on the control group using a
WRAS approved circulation pump which incorporates a
check valve to prevent backflow (see fig. 6).
3 Note to Installer
4 Installation
4.1.2 Mains Water Pressure
The DHW performance of an Glow-worm unvented cylinder
installation will correspond to the available mains water supply
pressure and flow rate. To achieve optimum performance from
the Glow-worm cylinder a suitable cold mains water supply
must be available, i. e. the measured static pressure from the
incoming mains water supply should be at least 2.0 bar. A
corresponding flow rate at least 20-25 l/min should be available.
NOTE: Mains water pressures will reduce during periods of
peak demand. Ensure that measurements are taken during
these periods.
Example:
If the measured cold mains supply pressure is 2 bar static and
the cold mains flow rate available is 30 l/min, the available flow
rate of mixed water at 40°C will be 25 l/min (from 15 l/min hot
water from the Glow-worm cylinder @ 60 °C together with 10 l/
min cold water @ 10°C).
The Glow-worm cylinder will operate satisfactorily with water
supply pressures below 2 bar although flow rates will be
reduced. If the supply pressure is below 1 bar the Glow-worm
cylinder should not be installed. Contact Glow-worm for details
on alternative hot water supply systems.
In order to minimise frictional losses minimum 22 mm bore is
recommended for new cold mains supply pipework into the
dwelling although satisfactory performance can be achieved
with 15 mm bore pipework.