The CARBOROBOT boilers capable to heat sanitary hot water(SHW) with separate hot exchanger. The hot exchanger placed direct on the side of the boiler. This hot exchanger work only close of the boiler body, with distance from the boiler it is not work.
The hot exchanger have input for the cold pipe water and output for the hot water, what we can use direct or for the buffer of hot water. If we open the hot water tap the cold pipe water will flow in the hot exchanger and the sensor will start the pump of hot exchanger. This pump will run until the tap is open. When the tap we close, the sensor will switch off the pump after some minutes(when the input tube will grow hot from the boiler).
The special feature of this equipment when the boiler body is cold the sensor will switch on the pump at that time also when the tap of hot water is closed. The pump will run until the boiler temperature will higher then switch off temperature of hot exchanger sensor. This temperature adjustable in the box of hot exchanger. It is expedient to regulate around 40°C to avoid the unwanted work of the pump.
If we use this type of hot exchanger than the regulation of the boiler need to make depend to the water temperature of the boiler. It's mean the regulation of the boiler not with the room thermostat, (in this case the boiler can be regulary cool down bellow than 40°C).
The hot water reserve in the boiler is big. One Farmer 40kW boiler with the heating water inside more than 1000kg. This hot mass can serve several hundred litre 50-60°C DHW in a short time. The boiler after falling of temperature of the heating water app. 10°C will start automatically and the SHW source. In the practice one powerful shower and one SHW tap in one time can operate. The hot exchanger module can be dismounted for the cleaning. The cleaning period depend to application time and the water hardness. We recommend to use lime prevention systems. This hot exchanger unit separate can be buy and possible to use for any CARBOROBOT boiler.

Heat capacity app. 30kW/h
Delta t. 40°C (60°C boiler temperature and 10°C pipe water temperature)
Flow through 12litre/min if water pipe pressure is 3 bar