ARENA 30 C
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In addition, shut-off valves should be installed between the boiler and the heating system to allow, if
necessary, the boiler to be isolated from the system. If a non-return valve is also installed in the domestic hot
water circuit, a safety valve must be fitted between the boiler and this circuit.
The discharge of the safety valve must be connected to a funnel or collection pipe, to avoid water leaking
onto the ground in the event of excessive pressure in the heating circuit.
Make the connections to the boiler so as its internal pipes are not subject to stress. For proper operation and
long-life of the boiler, the hydraulic system must be correctly proportioned and always complete with all the
accessories required to guarantee regular operation and conduction.
Upon request a connection kit can be supplied, simplifying connection to the system.
2.4 Characteristics of the boiler water
In the presence of water with hardness above 18 Clarke degrees, the water should be suitably treated, to avoid
any deposits in the boiler caused by hard water, or corrosion caused by aggressive water. It should also be
remembered that even minor deposits measuring just a few millimetres thick can cause, due to their low
thermal conductivity, significant overheating of the walls of the boiler, with consequent and serious problems.
The water must always be treated in the case of very large systems (with high water capacity) or systems with
the frequent inlet of recovered water. If, in these cases, the system needs to be partially or completely
emptied, it must be refilled with treated water.
Water System
Note
The boiler is designed for sealed systems only and must NOT be used on open vented systems.
Central Heating
Detailed recommendations are given in BS6798, BS5449, BS6700 and CP342 Part 2. Pipework not forming
part of the useful heating surface should be insulated to prevent any heat losses or possible freezing (i.e. in
roof spaces or ventilated underfloor spaces). Drain taps should be positioned at the lowest point of the
system in accessible locations to permit the whole system to be drained down. The drain taps should be in
accordance with BS2879. Copper tubing to BS2871, Part 1 is recommended for water carrying pipework.
Pipework in horizontal runs should have a gradient where possible to facilitate the removal of air. Ensure that
the boiler heat exchanger is not a natural point for air collection.
Make Up Water
Provision must be made for replacing water lost from the sealed system. Reference should be made to
BS6798, for methods of filling and making up sealed systems. There must be no direct connection between
the boiler's central heating system and the mains water supply. The use of mains water to charge and
pressurise the system directly, is conditional upon the Local Water Byelaws. Again any such connection must
be disconnected after use.
Domestic Hot Water
Always fit a scale reducer in "hard water areas" (18 clarke degrees or over)". A 15mm copper connection
point on the boiler for attaching to the main supply is provided. The maximum domestic water pressure for
the inlet supply is 10 bar (145 P.S.I.).
If the cold mains supply exceeds 5 bar (72 P.S.I.), a water governor
or pressure reducing valve must be fitted
by the installer into the mains supply in an inconspicuous but
accessible position preferable between 3 and 5 metres (10-16ft) before the appliance. Such a valve must be
approved by the Water Research Council.
Attention
- is drawn to the Model Water Byelaws.
Fittings manufactured from duplex (alpha-beta) brass are not acceptable for underground use and certain
water undertakings will not accept their use above ground.
Ensure all pipework is adequately supported.
Summary of Contents for ARENA 30 C
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