Ariston MICROCOMBI 23 MFFI, Installation And Servicing Instructions

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9
VR003A
R
ESIDU
AL
H
EAD
OF
THE
B
OILER
Particular attention should be paid to pipes passing through ventilated
spaces in roofs and under floors.
B
Y
-
PASS
:
The appliance includes an automatic by-pass valve, which protects the main
heat exchanger in case of reduced or interrupted water circulation through
the heating system, due to the closing of thermostatic valves or radiators.
S
YSTEM
D
ESIGN
:
This boiler is suitable only for sealed systems.
D
RAIN
C
OCKS
:
These must be located in accessible positions to permit the draining of the
whole system and should be fitted at all low points. The taps must be at least
15mm nominal size and manufactured in accordance with BS 2870:1980.
S
AFETY
V
ALVE
D
ISCHARGE
:
The discharge should terminate facing downward on the exterior of the
building in a position where discharging (possibly boiling water & steam) will
not create danger or nuisance, but in an easily visible position, and not
cause damage to electrical components and wiring.
The discharge must not be over an entrance or a window or any other type
of public access.
A
IR
R
ELEASE
P
OINTS
:
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 volume when the system is heated.
It can accept up to 6 litres (1.3 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. This should
be located on the return pipe work as close as possible to the pump inlet.
M
AINS
W
ATER
F
EED
- C
ENTRAL
H
EATING
:
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,
therefore a temporary method for initially filling the system and replacing lost
water during servicing in accordance with current Water Regulations and
bylaws must be provided
(F
IG
. 2.6). N
OTE
: The installer should ensure that
there are no leaks as frequent filling of the heating system can lead to
premature scaling of the main exchanger and failure of hydraulic
components.
D
OMESTIC
W
ATER
:
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, a scale reducer should also be used to reduce the
risk of scale forming in the domestic side of the heat exchanger.
C
ENTRAL
H
EATING
Detailed recommendations are given in BS 6798:1987 and BS 5449-1:1990,
the following notes are given for general guidance.
F
IG
. 2.6
Fill01