OSO HOTWATER 1327051, Installation Manual

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No. Description Dim.
1 Domestic hot water outlet (DHW out) ø22 mm
2 Coil FLOW ø22 mm
3 Coil RETURN ø22 mm
4 Temperature and Pressure relief valve 1/2”
5 Cold water inlet ø22 mm
6 Expansion relief valve connection 3/4”
2 3
1
4
5
2.15 Tundish
Recommended position of the tundish (8) is to
the right of the cylinder as seen from the front,
see illustration on previous page.
The tundish should be visible and positioned
away from electrical devices.
2.16 Discharge pipe
Connect the tundish outlet to the discharge
pipe. Install the tundish in a vertical position
within a maximum of 500 mm from the Tem-
perature and Pressure Relief Valve drain con-
nection. Ensure the expansion relief pipework
discharges through the tundish. Tundish pipe-
work must be 22 mm with a minimum vertical
length of 300 mm below tundish. Maximum
permitted length of 22 mm pipework is 9 m.
Each bend or elbow is equivalent to 0.8 m of
pipework. All pipework must have continous
fall and discharge in a safe, visible position.
If any doubt, refer to Building Regulation G3.
Discharge pipe must be dedicated to the cyl-
inder and must not be used for any other pur-
pose, see page 15.
2.17 Primary Flow and Return
The boiler primary flow and return connections
should be made to flow and return conections
on top of cylinder. To comply with regulations
governing the installation of indirect unvent-
ed cylinders, a motorised valve must be fit-
ted in the primary pipework. Your OSO unit
has been supplied with a two port motorised
valve, which will act as a positive energy cut-
out should the safety cut-out operate. The mo-
torised valve will also control the temperature
of the domestic stored water via the cylinder
thermostat, which is located in the electrical
box.
The unit can be installed on an “S” or “Y” plan
system. The motorised valve should be con-
nected to primary flow pipe. The motorised
valve has 22 mm copper connections. the max-
imum operating temperature of the primary
flow should be 82°C.
For electrical connection of the motorised
valve please read pt. 4 Electrical installation in-
structions.
6
Alternative pipework configurations
would be allowed to suit installation.