Keston System s30, Installation And Servicing Instructions

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12
Installation and Servicing
SECTION 1 - GENERAL
1.8 GAS SUPPLY
The local gas supplier should be consulted, at the installation
planning stage, in order to establish the availability of an adequate
supply of gas. An existing service pipe must NOT be used without
prior consultation with the local gas supplier.
The boiler MUST be installed on a gas supply with a governed
meter only.
A gas meter can only be connected by the local gas supplier or
by a Gas Safe Registered Engineer. In IE by a Registered Gas
Installer (RGII).
An existing meter should be checked, preferably by the gas
supplier, to ensure that the meter is adequate to deal with the rate
of gas supply required.
It is the responsibility of the Gas Installer to size the gas
installation pipework in accordance with BS6891:2005. Whilst
the principle of the 1:1 gas valve ensures the Keston range is
able to deliver it’s full output at inlet pressures as low as 14mb,
other gas appliances in the property may not be as tolerant.
When operating pressures are found to be below the minimum
meter outlet of 19mb these should be checked to ensure this is
adequate for correct and safe operation.
Allowing for the acceptable pressure loss of 1mb across the
installation pipework, it can be assumed that a minimum permitted
operating pressure of 18mb will be delivered to the inlet of
the appliance. (Reference BS 6400-1 Clause 6.2 Pressure
Absorption).
The external gas cock could further reduce the operating pressure
when measured at its test point. The pressure drop is relative to
the heat input to the boiler (kW), refer to graph below.
0
0.5
1
1.5
2
2.5
3
0 10 20 30 40 50
Pre
ss
ure
d
ro
p
(mb
ar
)
Heat Input to Boiler (kW)
Gas Cock Pressure Drop
IMPORTANT.
Installation pipes must be fitted in accordance with BS.6891. In IE
refer to IS.813:2002.
The complete installation MUST be tested for gas tightness and
purged as described in the above code.
1.9 WATER CIRCULATION SYSTEM
IMPORTANT.
A minimum length of 1 metre of copper pipe MUST be fitted
to both flow and return connections from the boiler before
connection to any plastic piping.
The central heating system should be in accordance with BS.6798
and, in addition, for smallbore and microbore systems, BS.5449.
WATER TREATMENT - see Section 1.16
1.10 BOILER CONTROL INTERLOCKS
Central heating systems controls should be installed to ensure
the boiler is switched off when there is no demand for heating, in
compliance with Building Regulations.
Heating systems utilising full thermostatic radiator valve control
of temperature in individual rooms should also be fitted with a
room thermostat controlling the temperature in a space served by
radiators not fitted with such a valve.
When thermostatic radiator valves are used, the space heating
temperature control over a living / dining area or hallway having
a heating requirement of at least 10% of the minimum boiler heat
output should be achieved using a room thermostat, whilst other
rooms are individually controlled by thermostatic radiator valves.
However, if the system employs thermostatic radiator valves on all
radiators, or two port valves, then a bypass circuit must be fitted
with an automatic bypass valve to ensure a flow of water should
all valves be in the closed position.
1.11 ELECTRICAL SUPPLY
WARNING.
This appliance must be earthed.
Wiring external to the appliance MUST be in accordance with
the current I.E.E. (BS.7671) Wiring Regulations and any local
regulations which apply. For IE reference should be made to the
current ETCI rules for electrical installations.
The mains supply to the boiler and system wiring centre shall be
through one common fused double pole isolator. For new heating
systems, and where practicable replacement boiler installations,
the isolator shall be situated adjacent to the appliance.
1.12 CONDENSATE DRAIN
Refer to Sections 2.12
A condensate drain is provided on the boiler. This drain must be
connected to a drainage point on site. All pipework and fittings in
the condensate drainage system MUST be made of plastic - no
other materials may be used.
IMPORTANT.
Any external runs must be in accordance with BS 6798.
The drain outlet on the boiler is sized for standard 21.5mm (3/4”)
overflow pipe. It is a universal fitting to allow use of different
brands of pipework.