Installation; Connection Of The Secondary Appliance; Connection Of The Primary Appliance Or Solar System; Connection On The Water Side - Worcester Greenstore TC Cylinder 150 litre Installation And Maintenance Instructions Manual

3.7

Installation

All hydraulic cylinder connections are suitable for 22 mm
pipes.
▶ Make connections with the compression fittings
supplied.
3.7.1

Connection of the secondary appliance

▶ Connect to the upper coil ( fig. 2 [2], page 6) using the
compression fittings supplied, either connection can be flow or
return, performance is identical either way. The heating circuit must
be positively pumped as gravity circulation is not possible.
▶ The heating circuit can be open vent or sealed system to a maximum
pressure of 6 bar. If the heating circuit is sealed an expansion vessel,
pressure gauge and pressure relief valve will be required if not
already part of the heating appliance.
▶ The heating appliance may be gas, oil or electric but must be under
effective thermostatic control. Uncontrolled heat sources such as
some AGAs, back boilers and solid fuel stoves are not suitable.
▶ Caution must be taken to prevent an air lock at time of commissioning
the unit, an air vent may be required.
▶ The coil must be able to be drained via a suitable valve.
3.7.2

Connection of the primary appliance or solar system

▶ Connect to the lower coil ( fig. 2 [10], page 6) using the
compression fittings supplied, either connection can be flow or
return, performance is identical either way. The heating/solar circuit
must be positively pumped as gravity circulation is not possible.
▶ The heating/solar circuit can be open vent or sealed system to a
maximum pressure of 6 bar. If the heating/solar circuit is sealed an
expansion vessel, pressure gauge and pressure relief valve will be
required if not already part of the heating appliance or solar system
equipment.
▶ The heating appliance may be gas, oil or electric but must be under
effective thermostatic control. Uncontrolled heat sources such as
some AGAs, back boilers and solid fuel stoves are not suitable.
▶ A solar system must be provided with a suitable controller and means
of thermostatic control with the solar sensors being fitted as per
TAB. 7, page 12, of this manual and the control manufacturer's
instructions.
In solar installations the mixing ratio of glycol & water
may increase the pressure drop through the coil.
▶ Caution must be taken to prevent an air lock at time of commissioning
the unit, an air vent may be required.
▶ The coil must be able to be drained via a suitable valve.
6 720 805 339 (2014/09)
3.7.3

Connection on the water side

▶ Install the cold water inlet control group as close as possible to the
cylinder cold water inlet, with the compression fittings supplied. The
mains supply must be able to provide the minimum pressure and flow
rates stated in specification table TAB. 4, page 8.
▶ The cold water inlet control group includes a 6 bar expansion relief
anti-vac valve. A discharge pipe must be installed and routed via a
tundish in accordance with current regulations.
NOTICE:
▶ If the cold water main is isolated internally or
externally for either emergency or maintenance
reasons, precautions should be taken to prevent
damage to the cylinder. The hot water isolation valve
located at the cylinder outlet should be closed off or
the cylinder should be drained down as per the
recommended procedure stated within this manual.
CAUTION: Damage through excess pressure.
▶ Never restrict the outlets of any safety valves.
▶ Install a drain valve at the cold water inlet.
3.7.4

DHW secondary circulation

Cylinders are equipped with a DHW secondary return connection.
▶ If no DHW secondary circulation is required, blank off and ensure a
water tight seal ( fig. 2 [4], page 6).
Seal and insulate the connection.
▶ When connecting DHW secondary circulation:
Install a DHW circulation pump approved for potable water and a
suitable non-return valve.
Due to the possibility of heat losses, DHW secondary
circulation is only recommended in conjunction with a
DHW secondary circulation pump that is time or
temperature-controlled. The circulation circuit must be
properly insulated.
To ensure safe DHW outlet temperatures thermostatic
mixing valves may be required. Guidance must be taken
from current regulations.
Thermal disinfection
Guidance must be taken from current regulations to ensure the risk of
Legionella bacteria growth is prevented.
Installation
13