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2. INSTALLATION
2.1 Health and safety regulations
Handling Operations Regulations 1992 defines
manual handling as: “any transporting or support-
ing of a load (including the lifting, putting down,
pushing, pulling, carrying or moving thereof by
hand or bodily force”. The Regulations set no spe-
cific requirements such as weight limits. However
common sense still has to be used based on an
ergonomic approach for each individual.
The Slimline should be transported and stored in a
vertical position.
2.2 Siting the Slimline
There are few restrictions on the siting of the OSO
Slimline, however it should not be sited anywhere
open to frost attack.
The unit should be placed on a stable flat surface
capable of withstanding the weight of the cylinder
when full and access must be allowed for mainte-
nance purposes. Provision should also be allowed
for the routing of the discharge pipe away from the
cylinder to an outside point according to building
regulation G3.
2.3 Component check list
Components supplied with the unit in a separate
accessory kit for site fitting:
•
Expansion vessel with wall bracket
•
Pressure reducing valve multibloc 3 bar with
expansion relief valve 6 bar
•
Motorized valve
•
Tundish (incl. screws)
•
Plastic cable clamp
•
Drain cock
Components factory fitted:
•
P&T valve
•
Immersion heater - 3 kW
•
Thermostat(s) / thermal cut-out
Documentation supplied:
•
Installation manual & service logbook
2.4 Supply requirements
An uninterrupted 22 mm cold water mains supply
is recommended, however if only a 15 mm supply is
available, this may be used provided there is suffi-
cient flow rate available. A minimum standing pres-
sure of 2.5 bar and a flow rate of 20 litres per minute
with a 1 bar dynamic pressure is recommended. The
cylinder will operate at lower pressures and flow
rates however the performance will be compro-
mised. The OSO unvented unit is designed for use
with supply pressure up to 12 bar. For pressures
over 12 bar an additional pressure reducing valve
must be fitted in the supply pipe to the unit.
2.5 Expansion vessel
An expansion vessel with wall bracket is supplied
with unit. The vessel accommodate expanded wa-
ter when the cylinder is heated and prevents the
cylinder reaching its maximum working pressure.
2.6 Preliminary wiring
Before final installation and pipe fitting it is rec-
ommended to feed the electrical wires to the
electrical box. The OSO Slimline is supplied with
all internal wiring factory fitted.
For more information about electrical installations
see chapter 4. ELECTRICAL INSTALLATION.
2.7 Pipework
Cold water supply:
1. To obtain the best performance from your
OSO unvented system it is advisable to feed
the unit with an uninterrupted supply.
2. Before connecting to the multibloc, flush the
cold supply pipework of all flux and debris.
3. Locate the water heater in a suitable position
to facilitate the installation of the cold water
supply, discharge fittings and pipework. Also
take into account access to the immersion
heater.
4. Fit a 3/4” - 22 mm elbow (not supplied) to
cold supply point so that the compression
fitting is vertical.
5. Fit a drain valve at the lowest point of the
cold water supply pipe (not supplied).
6. Fit a length of copper tube 22 mm to the
cold feed elbow to include a Tee piece if a
secondary return is required
7. Fit the Pressure Reducing Valve to the top of
the copper tube.
8. Connect 15 mm copper tube from the expan-
sion relief valve (4) and also from the T & P
valve (5) and join together in a Tee as shown
in illustration.
9. Fit the tundish (6) to the bottom connection
of this tee.
