Technical information

14
installation
Note:
• The distance between the cold feed and the open
vent pipe shall be no more than 150mm.
• The cold feed must be inverted as shown.
• The open vent pipe must be a minimum of 22mm
diameter.
• The cold feed pipe must be a minimum of 15mm
diameter.
• The cold feed and open vent pipes must rise
continuously and be unrestricted.
• The minimum distance from the top of the boiler
to the bottom of the F & E tank shall be no less
than 2m. Whilst the maximum distance shall be
not more than 27m.
• The distance between the bottom of the F & E
tank and the highest point of the open vent must
be no less than 500mm.
• The ow and return pipes from the boiler must
rise continuously and be unrestricted.
• The supply of water to the F & E tank should be
taken from the mains water supply via a suitable
oat operated valve. While the supply from the F
& E tank to the boiler/heating circuit (via the cold
feed) shall be unrestricted.
• The F & E tank must be adequately supported
and installed in accordance with relevant Building
Regulations.
Pump specication
The pump should be tted on the ow pipe from
the boiler and have isolating valves each side. A
variable duty pump should be set to give a tempe-
rature dierential of no greater than 20ºC.
Draining tap
A draining tap must be provided at all the lowest
points of the system which will allow the entire
system to be drained. A drain tap must also be
installed on the ow and return pipes immediately
above the boiler to ensure complete draining of the
primary ow and return is possible.
Drain taps shall be to the current standard of BS
2879.
Sealed water systems
A sealed system kit is available from Ariston. Installa-
tion instructions are supplied with the kit.
mWH
l/h
0
100
200
300
400 500 600 700 800 900
1000 1100
1200
1300
1400
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
12-18 kW
12 kW
18 kW
821 l/h = 20 Δ @ 19.1 kW
555 l/h = 20 Δ @ 12.9 kW
1.3 mWH
2.65 mWH
24 kW
1118 l/h = 20 Δ @ 26.0 kW
3.7 mWH
Pressure Loss Graphs through the boilers