Condensate Pipe Work; Internal Connections - Worcester GREENSTAR 24i Junior Installation, Commissioning And Servicing Instructions

The boiler is equipped with an internal by-pass.
The internal bypass is not intended to be a substitute for
an external system bypass.
An external automatic bypass should be used if the
system flow can be significantly adjusted or stopped by
zone valves and thermostatic radiator valves (TRV).
SHOWERS/BIDETS:
• Ensure that the shower is suitable for use with mains water pressure.
• If a shower head can be immersed in water or comes closer than
25mm from the top edge of a bath or shower tray spill over level then
an anti-syphon device must be fitted to the shower hose.
• Bidets with direct hot and cold mains water can be used (with the
approval of the local water authority) and must be the over rim
flushing type with shrouded outlets to prevent the fitting of hand held
sprays.
SEALED PRIMARY SYSTEM:
NOTICE: Artificially softened water must not be used to
fill the central heating system.
• The CH sealed system must be filled using a WRAS approved filling
loop or comply with figure 4 for system fill.
• Where the system volume is more than 100 litres or exceeds 2.65 bar
at maximum heating temperature, an extra expansion vessel (2) must
be fitted as close as possible to the appliance in the central heating
return.
• Pressurise the extra expansion vessel (2) to the same figure as the
expansion vessel built into the appliance.
• Do not use galvanised pipes or radiators.
SYSTEM FILL
Heating
return
Hose union
SV
Temporary hose
CV = Check Valve
SV = Stop Valve
Fig. 4 System fill
TYPICAL SEALED SYSTEM
1
2
3
4
Fig. 5 Existing build - Sealed system
6 720 802 047 (2013/05)
Mains
supply
CV CV
SV
Test point
6720643895-05.1Wo
5 5
5 5
4
6720643895-06.1Wo
NEW BUILD - SEALED SYSTEM WITH ZONE VALVES
The latest Part L1a regulation for new installations require separate zone
controls for the central heating.
1
2
6
M
3
4
Fig. 6 New build - Sealed system
1 Appliance expansion vessel - CH
2 Extra expansion vessel - CH return
3 Pressure relief discharge
4 Drain cock
5 Radiators
6 Zone valves
Table 6 Key to fig. 5 & 6
3.4

CONDENSATE PIPE WORK

NOTICE:
▶ Where a new or replacement boiler is being installed,
access to an internal "gravity discharge" point should
be one of the factors considered in determining boiler
location.
▶ The condensate pipe must be nominally
22mm Ø plastic pipe.
▶ The condensate pipe work must fall at least 52mm per
metre towards the outlet and should take the shortest
practicable route.
▶ Ensure there are no blockages in the pipe run.
Key to condensate illustrations
1 Condensate discharge from boiler
2 Soil and vent stack
3 Minimum 450mm and up to three storeys
4 Visible air break at plug hole
5 Sink or basin with integrated overflow
6 75mm sink waste trap
7 Condensate pump
* Condensate trap of 75mm already incorporated into the boiler

3.4.1 INTERNAL CONNECTIONS

In order to minimise risk of freezing during prolonged cold spells, the
following methods of installing condensate drainage pipe should be
adopted, in order of priority.
Wherever possible, the condensate drainage pipe should be routed and
terminated so that the condensate drains away from the boiler under
gravity to a suitable internal foul water discharge point such as an
internal soil and vent stack. A suitable permanent connection to the foul
waste pipe should be used.
PRE-INSTALLATION
5 5
5 5
4
11