The boiler is a buffer storage tank with 3 heaters (220V) with a power output of 9KW supplied by a motor cable. The pump is coupled with an Auraton control unit which starts the pump when the water has reached the desired temperature. The system is designed to work on the night rate (hot water accumulation in the buffer tank) and to distribute it in the system on the day rate. The problem is the control of the installation in antifreeze mode. I am missing an idea for a timer to start the heaters on the night-time tariff but only when the room temperature drops to <10 deg. and for a thermostat for the pump to switch it off when the room temperature reaches 10 deg. An example cycle should look like this: The room temperature drops to 5 °C, so the thermostat switches on the heaters, but not before 10 p.m. After 8 hours of operation, the water reaches approx. 80 °C, which activates the pump circuit. The timer should switch off the heaters even though the room temperature has not changed, as it will only rise after the pump has been running for some time. The pump will circulate water until the room temperature reaches 10 °C, but no longer than until the water in the circuit cools down to a temperature that does not provide heating power. Then (if it is < 10 °C) the heaters are switched on and the whole cycle repeats, which I assume may happen once in 2-3 days.
The biggest technical problem is the thermostat on the 400 V outlet which always switches on the heaters on the night rate at < 10 degrees, but at the same time switches them off at 6.00 a.m. while the interior temperature remains unchanged. The thermostat on the pump is also a conundrum, as it is supposed to switch it on at e.g. 80 °C (here the Auraton is sufficient), but immediately switch it off when the ambient temperature reaches 10 °C. In other words, this automation should be dependent on several variables, i.e. the temperature of the interior, heating water and time.
I would be grateful for suggestions as to how to control this.
The biggest technical problem is the thermostat on the 400 V outlet which always switches on the heaters on the night rate at < 10 degrees, but at the same time switches them off at 6.00 a.m. while the interior temperature remains unchanged. The thermostat on the pump is also a conundrum, as it is supposed to switch it on at e.g. 80 °C (here the Auraton is sufficient), but immediately switch it off when the ambient temperature reaches 10 °C. In other words, this automation should be dependent on several variables, i.e. the temperature of the interior, heating water and time.
I would be grateful for suggestions as to how to control this.
