Jet 120i Installation & Servicing Instructions Manual page 4

Water Supply
Bear in mind that the mains water supply to the
property will be supplying both the hot and cold
water requirements simultaneously.
It is recommended that the maximum water demand
is assessed and the water supply checked to
ensure this demand can be satisfactorily met.
Note: A high mains water pressure will not always
guarantee high flow rates.
Wherever possible the mains supply pipe should be
22mm. We suggest the minimum supply requirements
should be 0.15MPa (1.5 bar) pressure and 20 litres
per minute flowrate. However, at these values outlet
flow rates may be poor if several outlets are used
simultaneously. The higher the available pressure and
flow rate the better the system performance.
The cylinder has an operating pressure of 0.30MPa
(3.0 bar) which is controlled by the cold water
combination valve assembly. The cold water
combination valve assembly can be connected to a
maximum mains pressure of 1.6MPa (16 bar).
Outlet/Terminal Fittings (Taps, Etc.)
The cylinder can be used with most types of terminal
fittings. It is advantageous in many mixer showers
to have balanced hot and cold water supplies. In
these instances a balanced cold water connection
is available on the cold water combination valve
assembly (see Fig. 05, page 11). Outlets situated
higher than the cylinder will give outlet pressures
lower than that at the heater, a 10m height difference
will result in a 1 bar pressure reduction at the outlet.
All fittings, pipework and connections must have a
rated pressure of at least 6 bar at 80°C.
4
Limitations
The cylinder should not be used in association
with any of the following:
• Solid fuel boilers or any other boiler in which the
energy input is not under effective thermostatic
control, unless additional and appropriate safety
measures are installed.
• Ascending spray type bidets or any other class
1 back syphonage risk requiring that a type A air
gap be employed.
• Steam heating plants unless additional and
appropriate safety devices are installed.
• Situations where maintenance is likely to be
neglected or safety devices tampered with.
• Water supplies that have either inadequate
pressure or where the supply may be intermittent.
• Situations where it is not possible to safely pipe
away any discharge from the safety valves.
• In areas where the water consistently contains a
high proportion of solids, e.g. suspended matter
that could block the strainer, unless adequate
filtration can be ensured.
• In areas where the water supply contains chloride
levels that exceed 250mg/l.
Checklist
• Unvented cylinder
• Cold control pack
- Tundish
- Combination valve
- Tool - Element spanner
- Compression nuts & olives
- 2 Port motorised valve
• Literature pack
- Installation manual
- Guarantee card