Alpha Alpha CD50, User Instructions

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4 Alpha CD50
5 BOILER OPERATION
The operating sequence of the boiler is controlled by the selector switch on the control panel. With the switch set to (hot water
only) the boiler will only operate to provide domestic hot water, ideal for Summer use when central heating is not required.
Setting the selector switch to (central heating and hot water) the boiler will operate to provide both central heating and
hot water.
If the boiler is operating to provide central heating and a hot water tap is opened, the boiler will give priority to provide hot water.
Such an interruption in the central heating should not be noticed by any reduction in room temperature.
Note:
If a clock is fitted to the boiler, it will only control the operating times of the central heating. Hot water will always be
available when a tap is opened.
When the boiler is set to provide both central heating and hot water, it will respond to a demand for heat in the following sequence:-
The pump will start, the fan will start and the main burner will light.
The output of the burner is automatically controlled to suit the system demand.
When the temperature of the heating system water in the boiler reaches that set by the thermostat or the room thermostat is
satisfied, the main burner is turned off and after approximately 50 seconds the fan stops. The pump will continue to run to
remove any residual heat from the boiler.
When a hot tap is opened, hot water is provided instantly. When the temperature of the water in the storage cylinder falls to below
that set by the thermostat, the pump will start, the fan will start and the main burner will light to reheat the water in the storage cylinder.
Note: When the hot water temperature falls below approximately 48°C, the flow of hot water from the boiler is reduced. This
allows hot water to be supplied continuously until the water in the storage cylinder has been reheated.
The supply of hot water is instantaneous at the boiler, but the time taken to reach a tap will depend on the length of the pipe between
the tap and the boiler.
The flow of water to the hot taps will depend on the mains water pressure.
7 IMPORTANT NOTES
Thermostatic or pressure equalising type - When using these types of shower set the boiler domestic hot water thermostat
to maximum. The shower should then maintain a relatively constant temperature.
Manual bath mixer type shower - When using this type of shower set the boiler domestic hot water thermostat to setting 7,
This should avoid excessive temperatures at the shower.
Note: If you get unacceptable temperature variations with this type of shower, then a thermostatic or pressure equalising type
should be used.
6 USING A SHOWER
1. BOILER LOCATION
Always ensure the following clearances are available around the boiler:-
Top: 220 mm, Bottom: 250 mm, Sides: 10 mm, Front: 450 mm
If the boiler is installed in a cupboard or compartment, ensure that all ventilation openings are clear. Do not store any other articles
in the cupboard containing the boiler and never place any clothing or combustible material on or near the boiler or flue pipe.
2. FLUE TERMINAL
The terminal on the outside wall must not be allowed to be obstructed. If it is damaged, in any way, turn the boiler off and
contact your Service Engineer.
Note: The Alpha CD boilers are high efficiency condensing boilers and when operating vapour will be emitted from the
terminal. This is safe and quite normal.
3. MAINS FAILURE
In the event of an electrical supply failure the boiler will not operate. When the supply is restored, the boiler will return to normal
operation. Remember to reset the clock when the supply is restored.
If the mains water supply fails, there will be no hot water from the taps. The boiler will continue to provide central heating.
4. ADDITIONAL BATHROOM FITTINGS
Any equipment such as mixing valves, showers, bidets etc. must be designed to operate at mains water pressure. Contact your
local Water Authority for advice when considering purchasing such items.