
1-1 INTRODUCTION
This Handbook has been compiled to assist in the Installation and Operation of the OSO Dualstream domestic hot and cold
water system. The Installer of the system should give full operating instructions to the householder for the OSO Dualstream
System.
1-1.1 How the OSO Dualstream system works
Fig.1-1 is a schematic illustration of a typical OSO Dualstream system showing how it works.
Option A
is used when the accumulator is installed remotely from the unvented cylinder and requires an accessory pack
containing pressure reducing valve, expansion relief valve expansion vessel and bracket, available at additional cost and
should be ordered with the system.
1-1.2 System Contains
1.
An unvented hot water cylinder pre-plumbed with all valves and controls with easy access pipe connections for quick,
trouble-free installation.
2.
Cylinder Thermostat and High Limit Thermostat.
3.
An Accumulator (cold water storage) and associated fittings.
4.
One two port motorised valve for connection to heating system flow to cylinder (Indirect only).
5.
The OSO Dualstream is supplied with an adjustable pressure reducing valve. This means pressure to all mains water
outlets can be adjusted between 0.5 bar to 5 bar.
1-1.3 System Features
1.
All Taps and Showers are at maximum ‘Mains Pressure’.
2.
Equal pressure at Hot and Cold Taps.
3.
No pressure drop when more than one Tap is in use.
4.
More than 25% less pipework than traditional systems.
5.
No loft storage tank.
6
.
Completely sealed system - all Cold Taps are classed as wholesome water.
2
INTRODUCTION
1
Fig. 1-1 Schematic illustration
(Indirect unit)
Rubber expanding
bladder inside vessel.
Pressure is maintained
at maximum
‘Mains Pressure’.
Pressure relief valve
vents excess pressure
from Hot Water System.
Hot Water Cylinder is at
‘Mains Pressure’ due to
incoming cold.
Cylinder with immersion
heater. Water can be heated
by any conventional method.
Existing
Mains Supply
Hot Supply
Option A
Non-return valve. As
water is used system
is equalised to
maximum ‘Mains
Pressure’.
Boiler Return
Secondary Return
Boiler Flow
Air Pressure
Diaphragm
Accumulator
Mains Water