Ariston Genus 27 Plus Installation Instructions Manual page 10

Residual Head of the Boiler
Fig. 2.5
1
A: Gas inlet
B: C.H.W. return
C: C.H.W. flow
D: D.H.W. secondary return
E: D.H.W. flow
F: D.H. inlet
Fig. 2.5.1
10
Air Release Points:
These must be fitted at all high points where air naturally collects and must be
sited to facilitate complete filling of the system.
The appliance has an integral sealed expansion vessel to accommodate the
increase of water value when the system is heated.
It can accept up to 7 l (1.5 gal) of expansion water. If the heating circuit has an
unusually high water content, calculate the total expansion and add an additional
sealed expansion vessel with adequate capacity.
Mains Water Feed - Central Heating:
There must be no direct connection to the mains water supply even through a
non-return valve, without the approval of the Local Water Authority.
Filling:
A temporary method for initially filling the system and replacing lost water during
servicing and initial filling (complying to current water regulations and byelaws)
must be provided. The flexible hose must be removed once the system has been
filled.
Domestic Water
The domestic water must be in accordance with the relevant recommendation of BS
5546:1990. Copper tubing to BS EN 1057:1996 is recommended for water carrying
pipe work and must be used for pipe work carrying drinking water. The domestic hot
water temperature should be be adjusted to trip at 60˚C. This temperature will pre-
vent the formation of limescale in hard water areas.
Note: This appliance is capable of producing domestic hot water of up to
Secondary Return
The secondary return can be used as an option. A Non Return Valve (not supplied) must
be fitted to prevent back flow and a Bronze Pump will be needed in conjunction with a
Pipe Thermostat to circulate the hot water (both not supplied).
17
A B C D E
18
5
3
4
Others
users
2
70˚C. For extra security against scalding a thermostatic blending valve
may be installed on the domestic hot water outlet.
1 - Gas meter inlet cock
2 - Gas meter
3 - Gas meter outlet cock
16
4 - Internal gas cock
5 - Appliance gas inlet cock
6 - D.W. inlet cock
7 - D.H.W. expansion vessel
8 - cock
9 - Secondary return pump
F
Pressure
V
reducing valve
6
D. W. inlet
9
8 8
10
11
10 - Thermostat
11 - Time control clock
12 - Radiator control clock
13 - Holder
14 - Air release valve
15 - Drain valve
16 - T&P valve
17 - Safety valve
18 - Tundish
12
14
12
14
13
12
15
13
15
13
Drain tap
(at lowest point)
14
15
SH006A