2 flue and ventilation 3 water systems – Glow-worm Micron 80FF User Manual
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Diagram 3.1
Diagram 2.2
7056
2.3 Terminal Guard
A terminal guard is required if persons could come into contact
with the terminal or the terminal could be subject to damage.
If a terminal guard is required, it must be positioned to provide
a minimum of 50mm clearance from any part of the terminal and
be central over the terminal, see diagram 2.2.
A suitable guard, reference Type “K3”, can be obtained from:
Tower Flue Components Ltd.,
Morley Road,
Tonbridge,
Kent.
TN9 1RA
2 Flue and Ventilation
3 Water Systems
The installation of the boiler must comply with the requirements
of the current issue of BS6798, in Ireland, refer also to the
current edition of I.S.813 “Domestic Gas Installations”.
In GB it is necessary to comply with the Water Supply (Water
Fittings) Regulations 1999 (for Scotland, the Water Byelaws
2000, Scotland).
To comply with the Water regulations your attention is drawn to:
The Water Regulations guide published by the Water Regulations
Advisory Service (WRAS) gives full details of the requirements.
In IE the requirements given in the current edition of I.S.813
“Domestic Gas Installations” and the current Building Regulations
must be followed.
3.1 Frost Protection
There is a built-in frost stat in this boiler. See Protection Against
Freezing in Instructions for Use. Where other parts of the
system are vulnerable this should also be considered as specified
in the current issue of BS5422.
3.2 Pump
The pump, with integral valves, should be fitted in the heating
flow pipework from the boiler, it should be set to produce a
temperature difference of 11
o
C (20
o
F), between the flow and
return, with the boiler thermostat set at “MAX”, which is about
82
o
C (180
o
F).
The pressure loss of the boiler at 30.6 litre/minute giving 11
o
C
temperature difference is 950mm head of water.
High resistance microbore systems may require a higher duty
pump.
3.3 Bypass
A bypass is usually unnecessary on systems using a 3 port
diverter valve since one port will remain in the open position at
all times. This allows satisfactory operation of the pump overrun.
However if thermostatic radiator valves are fitted to all radiators
or two port valves are used a bypass is required.
The bypass connection must be at least 2 metres away from the
boiler.
The flow through the boiler must not be allowed to fall such that
there is a temperature difference greater than 20
o
C between the
flow and return.
3.4 Water System
For an open vented system the boiler must be supplied from an
unrestricted water supply taken from a feed and expansion
cistern fitted at a maximum height of 27 metres above the boiler.
The cold feed must be 15mm minimum size.
It is important that the relative positions of the pump, cold feed
and open vent are as shown in diagram 3.1.
The unrestricted open vent from the boiler must rise continuously
to discharge over the feed and expansion cistern.
3.5 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”.
3.6 Cylinder
For all systems supplying domestic hot water the cylinder must
be indirect. It is recommended that the cylinder be fitted with
some form of temperature control.