14
Fig. 9 - External soakaway
Fig. 8 - External gully
Alpha InTec C and X - General Boiler Information
Open end of pipe
diverted into gully
below grid but above
water level
Use waterproof
pipework insulation
in very exposed
positions
Ensure pipe is
adequately supported
Plastic pipe
Minimum gradient 2½°
Ground level (either/or)
22mm termination from boiler, increase to 32 mm if external
2½ fall
O
25mm
300mm
Two rows of 3 x 12mm
holes at 25mm centres,
50mm from the bottom
of the tube. Holes to face
away from house.
Cement mortar sealing
100mm plastic tube
Bottom of tube sealed
Soakaway depth 400mm
filled with limestone chippings
500 mm min.
3.11 DOMESTIC HOT WATER SYSTEM
The minimum fl w rate needed for the fl w switch and burner to operate is 2.5 litres/min.
The incoming mains water pressure should be between 0.2 and 8 bar to ensure efficient operation. If the pressure is above 7
bar a pressure reducing valve must be fitted
Following Part L Building Regulations, where the mains water hardness exceeds 200 parts per million, provision should be
made to treat the feed water to the hot water circuit of combination boilers to reduce the rate of accumulation of limescale.
To ensure economic use, the pipe runs between the boiler and taps should be in 15 mm copper pipe and be as short as
possible. Where possible the pipework should be insulated to reduce heat loss.
All taps and mixing valves used with the hot water system must be suitable for operating at a mains pressure of up to 8 bar.
Showers -
A shower may be used with the boiler if required.
If a loose or fl xible head type shower is used it may require the fitting of a double check valve, to comply with Water Bye Law 17.
Bidets -
No anti-syphonage arrangements are necessary, provided the outlets are shrouded and it is not possible to attach
a temporary hand held spray. A supply of direct mains fed hot and cold water is permitted provided the appliance is of the
over-rim flushing typ .
Before the mains water supply pipe is connected to the boiler, it should be thoroughly flushed out to void the danger of dirt
or foreign matter entering the boiler.
Seasonality valve (C models only) -
This valve maintains the hot water temperature (factory set) for both summer and
winter conditions by automatically changing the fl w rate through the boiler. However, if adjustment of the setting is required,
refer to Section 5.6.2.
