The company reserve the right to alter size, shape and specification without prior notice
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When setting variable temperatures please be aware that the heating system will take some time to heat up from
cold and similarly will remain hot for some time after the temperatures are reduced or the system is switched off.
To optimize comfort levels and minimize energy consumption it is suggested to activate the boiler 30 minutes
before the set temperature in heating system is required and to reduce temperature or switch off 30 minutes
before the lower temperature is desired.
5.4. Domestic hot water priority
Domestic water heating has priority over central heating. When the domestic hot water temperature sensor calls
for heat, the central heating circulation pump is switched off and domestic hot water heating circulation pump is
switched on.
The setting of secondary (DHW) temperature regulates the desired primary temperature in the boiler. The primary
water is set at 15°C higher than the desired secondary (DHW) temperature. (Independent of central heating
curve).
The boiler heats the cylinder until the desired secondary (DHW) temperature is reached, the elements will then
power down and the pump overrun operates - see page 24.
If the central heating is on, when the desired secondary (DHW) temperature is reached, the desired primary
temperature reverts to the value from the heating curve.
If the central heating is off, when desired secondary (DHW) temperature is reached, the desired primary
temperature reverts to the stand-by value of primary water temperature in the boiler.
If the cylinder probe repeatedly calls for domestic hot water heating, the desired water temperature in the boiler is
automatically set to 15°C higher than the desired secondary (DHW) temperature.
There is a 5°C difference between switch on and switch off for secondary (DHW) heating. If the desired
temperature of hot water cylinder is 60°C, the domestic hot water is activated only when the cylinder store
temperature cools to 55°C. Domestic hot water heating is switched on until the hot water temperature reaches
60°C.
During periods of simultaneous demand for space heating and domestic water heating, the boiler will alternate
between the two every 30 minutes.
4.5. Protection from freezing
4.5.1. Domestic hot water
If the boiler is on, protection from freezing of the domestic hot water cylinder switches on automatically when the
cylinder temperature reads a value below 5°C, signaling switching on by blinking display, as well as the LED
diode of the heater and water heating, regulating the cylinder temperature to 5°C.
4.5.2. Central heating
To protect the entire central heating system from freezing (if a building is to be left empty for an extended period
of time during cold weather), set the boiler to standby mode. The room thermostat or central heating programmer
must be set to freezing protection mode (usually 5 to 7˚C, depending from room thermostat manufacturer), this
will allow pump to circulate heated medium through central heating system.
