Site Requirements - Baxi 47 075 35 Installation & Servicing Instructions Manual

2. Your attention is drawn to:
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".
3. The Water Regulations recommendations for England and Wales prohibits backflow from appliances into the wholesome water
supply due to thermal expansion. However this type of instantaneous combination boiler, with less than 15 litres of stored capacity,
does not require any backflow prevention device as any thermal expansion is accommodated within the appliance. It is possible in
certain circumstances that other cold water demands (e.g. washing machines, flushing of W.C.s) may affect the DHW function of
the boiler. In these instances the fitting of a backflow prevention device and expansion vessel is recommended.
4. Also if there is an existing check valve, loose jumpered stop cock, water meter or water treatment device already fitted to the
wholesome water supply connected to the boiler domestic hot water (DHW) inlet supply then a suitable expansion device may be
required.
5. The boiler's maximum working mains pressure is 8 bar, therefore all pipework, connections, fittings, etc. should be suitable for
pressures in excess of 8 bar. A pressure reducing valve must be fitted for pressures in excess of 8 bar. The manufacturer of any
outlet fittings, such as a shower valve, may require a lower maximum pressure. The pressure reduction must take account of all
fittings connected to the DHW system.
Fig. 7
6.9 Showers
1. If a shower control is supplied from the appliance it should be of the thermostatic or pressure balanced type. Thermostatic type
shower valves provide the best comfort and guard against water at too high a temperature. Existing controls may not be suitable ­
refer to the shower valve manufacturer.
6.10 Hard Water Areas
1. If the area of the installation is recognised as a HARD WATER AREA then a suitable device should be fitted to treat the mains
water supply to the boiler. Contact your Water Distribution Company for advice on suitable devices.
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7.0 Site Requirements
7.1 Location
1. The boiler may be fitted to any suitable wall with the flue passing through an outside wall or roof and discharging to atmosphere in a
position permitting satisfactory removal of combustion products and providing an adequate air supply. The boiler should be fitted
within the building unless otherwise protected by a suitable enclosure i.e. garage or outhouse. (The boiler may be fitted inside a
cupboard­see Section 7.3).
2. If the boiler is sited in an unheated enclosure then it is recommended to leave the ON/OFF Selector Switch in the domestic hot
water and central heating position to give frost protection.
3. If the boiler is fitted in a room containing a bath or shower reference must be made to the relevant requirements. In GB this is the
current I.E.E. Wiring Regulations and Building Regulations. In IE reference should be made to the current edition of I.S. 813
"Domestic Gas Installations" and the current ETCI rules.
4. If the boiler is to be fitted into a building of timber frame construction then reference must be made to the current edition of Institute
of Gas Engineers Publication IGE/UP/7 (Gas Installations in Timber Framed Housing).
*This is the MINIMUM recommended dimension. Greater clearance will aid installation and maintenance.