Alpha InTec2 20SE Installation And Servicing Instruction page 24

Comfort or Easy-Stat RF receiver and Digital or Mechanical Clock installation
1. Remove the screw securing the connections cover labelled 'connections for 230V controls' to expose the receiver/clock
connections. See Fig. 4.15.
2. Remove the link between the red wires 3 and 4 and plug all wires on to their corresponding numbers on the receiver or
clock.
3. Locate the receiver or clock onto the two pins and using the two screws provided fix into position.
4. Remove the round blanking panel from the cover panel and re-fit the control panel cover in reverse order.
External Sensor – Weather compensation feature
The Alpha InTec² boilers have a built in weather compensation feature which is automatically activated when the external
sensor is fitted – Part No 3.022383. When fitted the weather compensation sensor allows the boiler to control the maximum
primary flow temperature to the heating circuit according to the outside temperature, heating the property more effectively
and efficiently.
Operation
During a central heating on period the sensor monitors the external temperature and modulates the boiler heating output to
give the correct flow temperature to maintain the required room temperature. If the external temperature drops then the flow
temperature will increase, if the external temperature increases then the flow temperature will decrease. This reduces the
amount of wasted energy and reduces gas consumption.
When an external weather sensor is fitted the CH temperature control dial will no longer adjust the flow temperature in °C,
instead the display will show a scale of 1 to 9. Each number corresponds to a line on the graph in Fig. 4.18 e.g. line 6 will
give a flow temperature of 60°C when the external temperature is 10°C.
Notes: 1. The temperature of the radiators will vary depending on the outside temperature; the required room temperature
will still be maintained by the room thermostat.
2. The weather compensation sensor can only be used on an InTec² SE boiler when the Alpha diverter valve kit is
used, otherwise the DHW temperature will be affected.
System
temperature
(°C)
24
Alpha InTec² 20SE and 30SE - Installation
Connections cover
Comfort / Easy-Stat receiver
Blanking panel
Max.
Min.
27 20 15
Fig. 4.17
9 8 7 6 5
4
3
2
1
10 5 0 -5
External temperature (°C)
Fig. 4.18
-10 -15 -20