10
136,8
3 6 0
143
741
115
1 5 0
3 5
884
1 5 0
4 0 0
27
27
740
739
27
Wall Mounted,
Fanned Flue System Boiler
MYNUTE 20 VHE
RETURN
GAS
FLOW
3A.10 INHIBITORS
Vokera recommend that an inhibitor - suitable for use with
aluminium heat exchangers - is used to protect the boiler
and system from the effects of corrosion and/or electrolytic
action. The inhibitor must be administered in strict
accordance with the manufacturers instructions*.
*Water treatment of the complete heating system - including
the boiler - should be carried out in accordance with I.S.
813 and the Domestic Water Treatment Association’s
(DWTA) code of practice.
3A.11 APPLIANCE PIPEWORK CONFIGURATION
(fig. 5)
The appliance ‘flow’ and ‘return’ connections can be
configured to suit the following:
1. Top outlet connection
2. Bottom outlet connection
3. Top (flow), bottom (return) connection
4. Top (return) bottom (flow) connection.
3A.11.1 FEED AND VENT PIPEWORK
The feed and vent pipe work from the boiler to the F&E
(Feed & Expansion) tank should be configured as shown
in figure 4A using a 22mm combined feed and vent pipe.
NOTE
●
The combined feed and vent pipe must rise continuously
and be unrestricted.
●
The diameter of the combined feed and vent pipe shall
be 22mm.
●
The minimum distance from the top of the boiler to the
bottom of the F&E tank shall be no less than 1-metre,
whilst the maximum distance shall be no greater than
30-metres.
The supply of water to the F&E tank should be taken from
the mains water supply via a suitable float operated valve,
whilst the supply from the F&E tank to the boiler/heating
circuit (via the combined feed and vent pipe) shall be
unrestricted.
3A.11.2 ALTERNATIVE CLOSE-COUPLED
ARRANGEMENT
If necessary or if preferred, a close-coupled arrangement
for the feed and expansion pipe work can be used as an
alternative to a combined feed and vent pipe. The
configuration of the close-coupled pipe work shall be as
shown in figure 4B.
NOTE
●
The distance between the cold feed pipe and the safety
vent pipe shall be no more than 150mm
●
The cold feed pipe must be inverted as shown in fig. 4B
●
The safety vent pipe must be 22mm in diameter
●
The cold feed pipe must be 15mm diameter
●
The cold feed pipe and safety vent pipe must both rise
continuously and be unrestricted.
●
The minimum distance from the top of the boiler to the
bottom of the F&E tank shall be no less than 1-metre,
whilst the maximum distance shall be no greater than
30-metres.
●
The distance between the bottom of the F&E tank and
the highest point of the safety vent pipe must be no
less than 500mm.
The supply of water to the F&E tank should be taken from
the mains water supply via a suitable float operated valve,
whilst the supply from the F&E tank to the boiler/heating
circuit (via the cold feed pipe) shall be unrestricted.
3A.11.3 REMOTE CONNECTION
It’s permissible to connect the feed and vent pipe work
remote from the appliance, providing it’s connected to the
primary heating pipe work as shown in figures 4C/4D.
NOTE
The instructions for a combined feed and vent
installation (3A.11.1) or close-coupled arrangement
(3A.11.2) still apply when connecting the feed and vent
pipe work remote from the appliance.
3A.12 DECLARATION OF CONFORMITY
A Declaration of Conformity (as defined in I.S. 813) must
be provided on completion of the installation
A copy of the declaration must be given to the responsible
person and also to the gas supplier if required.
Fig. 5
Fig. 6
