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2000225065A
5 Domestic Hot Water System
General - All domestic hot water circuits, connections, fittings
must be in accordance with the relevant standards and water
supply regulations.
For GB: Guidance G17 to G24 and recommendation R17 to
R24 of the Water Regulations Guide.
For IE: The current edition of I.S.813 "Domestic Gas Installations".
5.1 Water Pressure
The maximum working pressure of the domestic hot water
circuit is 10 bar. If the cold water supply pressure exceeds this,
then a pressure-reducing valve must be fitted in the supply to
the boiler.
5.2 ‘Hard’ Water Areas
The temperatures within the heat exchanger are limited by the
boiler control system to minimise scale formation within the hot
water pipework. However, in areas where the water is ‘hard’
(i.e. more than 200mg/litre), it is recommended that the hot
water setting is reduced and that a scale reducer is fitted.
Refer to the manufacturer’s instructions or consult the local
water company for additional advice.
5.3 Domestic Water Flow Rate
The water flow rate is restricted to a maximum 10 l/min (24cxi)
12 l/min (30cxi) and15.5 l/min (38cxi) by a restrictor fitted during
boiler installation, see diagram 8.2.