Glow-worm Ultimate 30FF - Manual (Page 9)

9 221518L
Diagram 3.1
3 Water Systems
1000
750
500
250
11.5
0
0 5 10 15 20 25 30
Flow rate (litres/minute)
Water pressure loss (mm head of water)
6809
The insertion point indicates the flow rate required to achieve
11°C temperature difference
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
If the position of the boiler is such that it may be vulnerable to
freezing it should be protected as specified in the current issue
of BS5422. It is recommended that a frost protection thermostat
be fitted.
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 can be found from diagram 3.1.
High resistance microbore systems may require a higher duty
pump.
3.3 Bypass - Fully Pumped and Sealed Water
System
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 27metres 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 3.2.
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".
The domestic hot water service must be in accordance with the
current issue of BS5546, refer also to the current issue of
BS6700.
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.
3.7 Gravity Domestic Hot Water with Pumped
Heating
Important: If domestic hot water is to be provided by a gravity
circulation to the cylinder the blanked off connections must be
opened and used, using 22x28mm connections, see diagram
3.3.
3.8 Fully Pumped Heating and Domestic Hot
Water
The connections for this type of system MUST be as shown in
diagram 3.2 and 3.4.
3.9 Inhibitor
Attention is drawn to the current issue of BS5449 and BS7593
on the use of inhibitors in central heating systems.
If an inhibitor is to be used, contact a manufacturer or Glow-
worm, for their recommendations as to the best product to use.
When installing in an existing system take special care to drain
the entire system, including radiators, then thoroughly cleaning
out before installing the boiler whether or not adding an inhibitor.
3.10 Sealed Water Systems
The installation should comply with the appropriate requirements
of the current issue of BS4814, BS5449, BS6759, BS6798 and
BS7074 Part 1 and 2, see diagram 3.5 for a suggested layout.
3.11 Safety Valve
A safety valve must be fitted to a sealed water system.
It shall be preset, nonadjustable with a lift pressure of 3bar,
incorporating seating of a resilient material, a test device and a
connection for drain.
The drain from the safety valve must be routed clear of any
electrical fittings and positioned so that any discharge can be
seen.