
User's
Instructions
Alpha CombiMax 350 and 600
Unvented Hot Water Store
for use with the
Alpha 240/280 Range of Gas Fired Combination Boilers
For Technical help or for Service call ...
ALPHA HELPLINE
Tel: 0870 3001 964
Nepicar House, London Road,
Wrotham Heath, Sevenoaks,
Kent TN15 7RS
These instructions must be used in conjunction with the Installation instructions provided
with the selected combination boiler.
Building Regulations
Certificate No. ETC 03198
Leave these instructions with the User

1 DESCRIPTION
The CombiMax 350 and 600 are wall mounted unvented hot water storage cylinders for use only with the Alpha 240/280 range
of gas fired combination boilers.
The CombiMax will provide constant hot water at temperatures of up to 56°C for as long as required.
2 USER CONTROLS
If applicable, pull the controls panel forward and down to gain access to the controls.
There are no separate user controls provided for the CombiMax and all the boiler controls are used as described in the
instructions supplied with the boiler, with the exception of the domestic hot water thermostat.
The domestic hot water thermostat must always be set to the maximum setting. A label has been supplied which should have
been positioned over the domestic hot water thermostat knob, as shown below, to ensure the maximum setting is maintained.
Alhpa 240P and Alpha 280P
Pilot and Burner
Viewing Window
Central
Heating
Thermostat
Alpha 240E and 280E
IMPORTANT
THERMOSTAT0THERMOSTAT0SELECTOR GAS
0
This hot water
thermostat must
always be set at
maximum
(i.e. turned fully
clockwise)
Domestic
Hot Water
Selector
Switch
Gas
Control
Thermostat
()set at maximum
IMPORTANT
THERMOSTAT0THERMOSTAT0SELECTOR
0
This hot water
thermostat must
always be set at
maximum
(i.e. turned fully
clockwise)
OFF
Indicator
Neons
Burner
Viewing Window
RESET
RESET
2
3
1
04
bar
System
Pressure
Gauge
2
3
1
04
bar
Clock
(if fitted)
Clock
(if fitted)
System
Pressure
Gauge
Central
Heating
Thermostat
Domestic
Hot Water
Thermostat
Selector
Switch
White
Reset
Button
Indicator
Neons
Red
Reset
Button
()set at maximum
2

Alpha 240X
3 COMBIMAX OPERATION
Refer to the instructions supplied with the boiler for full details of the operation of the boiler.
The CombiMax will supply hot water provided the selector switch on the boiler is set to either
Note: The clock on the boiler (if fitted) only controls the operating times of the central heating, not domestic hot water - DHW is available
continuously, unless an external clock has been fitted to control the operating times of the domestic hot water.
Domestic hot water supply always takes priority over central heating. If a demand for hot water is required during a central heating period,
the boiler will automatically switch to the hot water mode until the demand is satisfied, i.e. storage water is to the required temperature. This
interruption in the central heating is only when the demand for hot water is present and should not be noticed by the User.
When there is a demand for hot water (by opening a hot tap or temperature of the stored hot water is below the thermostat
setting) the store pump starts and the burner lights, heating the mains water by the DHW heat exchanger. When the water in
the store reaches a temperature of approximately 56°C the store thermostat switches the store pump off.
When a hot tap is opened, hot water is supplied from both the store and boiler. When the temperature within the store falls
below the outlet thermostat setting, the hot water flow from the store is stopped and hot water is supplied (at a reduced rate)
from the boiler only.
or .
4 HO T WATER USE
The supply of hot water is almost instantaneous at the CombiMax, but the time taken to reach a tap will depend on the length of
the pipe between the tap and the CombiMax.
The CombiMax will supply hot water at flow rates up to 18 litres/min. providing the stored hot water is up to the temperature set
by the thermostat. When the stored hot water is below the thermostat setting the flow of hot water at the tap is reduced to
approximately half the maximum flow rate, but the temperature of the hot water is maintained for as long as is required.
However, the flow rate is dependent on the mains water pressure, and the length and resistance of the pipework to the hot water outlets.
5 USING A SHOWER
Thermostatic or pressure equalising type - When using these types of shower, as the CombiMax maintains a constant flow temperature,
the boiler domestic hot water thermostat must be set to maximum, the shower should maintain a relative constant temperature.
Manual bath mixer type - When using this type of shower, care should be taken to establish a setting of the shower control to
give an acceptable temperature at the shower before entering. If you get unacceptable temperature variations with this type of
shower, then a thermostatic or pressure equalising type should be used.
6 CLOCK (if fitted)
If a clock is fitted to the boiler control panel, this will allow you to set the time at which the boiler will operate to provide central
heating. It does not affect the supply of domestic hot water from the CombiMax which is always available whatever the setting
on the clock. Details on setting the clock for central heating are detailed in the instructions provided for the boiler.
If an external clock is fitted, this may control both the central heating and supply of hot water from the CombiMax or only the
supply of hot water. Your installer should have informed you of this and how to operate the clock.
Note: When the clock used to set the operating times of the CombiMax is in an OFF position the CombiMax will not operate,
i.e. hot water will only be supplied from the water left within the storage cyliner. Therefore the OFF periods should be set at
times when hot water will not be required.
3

7 ELECTRICAL SUPPLY
The CombiMax requires a 230/240 V ~ 50 Hz supply, fused at 3 A if a 13 A 3-pin plug is used or a 5 A fuse if any other type of
plug is used.
To connect a plug:-
The colour of the wires in the mains lead of the boiler may not correspond with the coloured markings identifying the terminals
in your plug. In this case proceed as follows:-
The wire coloured green and yellow must be connected to the terminal in the plug that is marked with the letter E, or by the
earth symbol , or coloured green or green and yellow.
The blue wire must be connected to the terminal which is marked with either the letter N or coloured black.
The brown wire must be connected to the terminal which is marked with the letter L or coloured red.
THE APPLIANCE MUST BE EARTHED.
If an immersion heater has been fitted, refer to the instructions supplied with the heater.
8 GAS SAFETY REGULATIONS
Gas Safety (Installation and Use) Regulations:It is the law that all gas appliances are installed and serviced by a competent person, ie CORGI registered personnel. Failure to
install or service appliances correctly could lead to prosecution. It is in your interest and that of safety to ensure compliance
with the law. The manufacturer's instructions must not be taken in any way as over-riding statutory obligations.
9 IMPORTANT NOTES
1. COMBIMAX LOCATION
Always ensure the following clearances are available around the boiler:-
Top: 220 mm, Bottom: 250 mm (350 mm if immersion heater fitted), Each side: 5 mm, Front: 450 mm
Do not store any other articles in the cupboard containing the CombiMax and never place any clothing or combustible material
on or near the CombiMax, 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. In cold weather, vapour may be emitted from the terminal. This is quite normal.
3. MAINS FAILURE
In the event of an electrical supply failure the CombiMax will not operate (although hot water will be available until the stored
hot water has been used). When the supply is restored, the boiler will return to normal operation. However, in the case of the
Alpha boilers with a pilot, check that the pilot is alight by viewing through the window and if not, refer to the boiler lighting
instructions. 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 provided 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
plumbing merchant or Installer for advice when considering purchasing such items.
5. CLEANING
To maintain efficient and safe operation of your CombiMax and boiler, routine servicing is essential.
For advice on servicing contact:- The Alpha Helpline: 01322 669443.
7. GAS LEAK
If a fault or gas leak is suspected, turn off the gas supply. Do not touch any electrical switches, do not smoke and extinguish all
naked flames. Contact your local Gas Region immediately.
8. PRESSURE RELIEF VALVES
If the central heating or hot water system overheats and steam or water is discharged from the pipe connected to the valve or
from the tundish, turn the CombiMx and boiler off and contact your Service Engineer. Your Installer should have told you where
these pipes terminate.
9. IMMERSION HEATER
If an immersion heater has been fitted, it must only be switched on in an emergency, i.e. if the boiler/CombiMax is not working.
Alpha Therm Limited.
Nepicar House, London Road, Wrotham Heath
Sevenoaks, Kent TN15 7RS
email: info@alphatherm.co.uk
website: www.alpha-innovation.co.uk
Manual compiled and designed by Publications 2000, Tel (01670) 356525
These instructions have been carefully prepared but we reserve the right to
alter the specification at any time in the interest of product improvement.
© Alpha Therm Limited 1999.
Part No. 0001057/3
06/99/D116