Potterton Promax HE Store 90 Litres Installation & Servicing Instructions Manual page 20

2.4 Condensate Drain Pipe
Before fitting, fill the condensate trap with water.
Fit the steady bracket (with round hole) for the condensate
trap to the lower pair of holes in the left hand cylinder side
panel. Snap the C-shaped bracket into the groove in the
condensate connector. Insert the condensate trap into the
steady bracket and fit the C-shaped bracket to the upper
pair of holes in the left hand cylinder side panel.
Ensure that the washer seal is in place as indicated and
tighten the large nut.
The condensate pipe should be run in 21.5/22.0 mm
diameter plastic material suitable for operation at 60° C.
Solvent weld PVC overflow is recommended or a PP
system can be used. Copper tube must not be used. Do
not use push-fit plastic pipe.
Use the flexible pipe provided to connect to 21.5mm PVC
pipe; alternatively a Marley or Plumb Center elbow can be
used to direct the condensate pipe through the LH side
panel (see Fig. 10a). When using the Osma PVC overflow
system, a 3/4 -to-22mm adaptor No. 158 may be required.
Internal pipework should have a bore diameter no smaller
than 14 mm.
External pipework should be kept to a minimum, and have
a bore diameter no smaller than 32 mm.
Ideally the condensate pipe should be run internally to the
house soil and vent stack or to a waste pipe. Alternatively,
the condensate may be discharged into the rainwater
system, or a purpose-built soakaway.
All connecting drainage pipework must have a fall of at
least 50 mm per metre run. It is recommended that the
pipe is insulated if run externally to minimise the effects of
freezing, and that a plastic insert is fitted that provides a
siphon/weir action to encourage the water to flow in
intermittent bursts rather than dripping continuously.
Note: Connection of a condensate pipe to a drain may be
subject to local building regulations.
Manual Air Vent
Using the manual air vent, thoroughly vent air from top
of the heat exchanger when filling the system to save
time during the boiler commissioning. Note: 1/4" dia.
manometer tube fits the manual vent.
Central Heating Pump & System By-pass
The central heating pump is factory fitted and an
automatic system by-pass is provided. The boiler can be
used in systems controlled by thermostatic radiator
valves (TRVs) but it is essential that the by-pass isolating
valve is fully open.
The circulating pressure and flowrate available for the
central heating system is shown opposite with the by-
pass in circuit.
20
Boiler
Condensate
Connection
Fill up the Condensate
Trap with water, then
fit to the boiler
Lower Nut
Optional
Route -
Condensate
Fig. 10a
Washer Seal
Condensate
Drain Pipe
500mm supplied
(suitable for 21.5mm
overflow pipe)
Promax Store
Optional
RWC
Route -
DHW
© Baxi Heating UK Ltd 2006