Sobna enota Seltron RCD

When and why is the “Fireplace” feature used?

If the RCD room unit is installed in the same room as the fireplace, switching off of central heating can occur. That is, the fireplace can heat the room to a temperature that exceeds the set desired temperature on the room unit, and consequently, all heated area is switched off. In order to avoid the above problem, the new RCD unit has an integrated “Fireplace” function..

Room unit RCD with fireplace feature
This function allows the impact of room temperature on the operation of the room heating control to be temporarily switched off. When the “Fireplace” function is activated, the heating control operates on the basis of outdoor temperature.

The “Fireplace” function on the RCD room unit is activated by pressing the Party button for 10 seconds. The flashing “house” symbol on the room unit display indicates that the function is active. The “Fireplace” function operates at least for the time set by the parameter S1.13. After this time, it operates for as long as the measured room temperature exceeds the set desired room temperature.

Digital room unit SELTRON RCD2.

How to quickly heat a room?

The solution is the activation of the “BOOST” function

When for any reason we do not use the room sensor or room unit with weather-controlled heating controllers, such as, for example, CMP, WDC, WXD, KXD etc. or they are not connected, a room temperature deviation occurs when switching the time interval from night-time to living room temperature. The controller simply does not receive information that the rooms have cooled during the reduced – night-time heating, and that they should be heated for some time at a higher temperature than required by the selected heating curve and the current outdoor temperature.
This problem can be greatly reduced or completely eliminated with the help of a special “BOOST” function that is integrated into all Seltron weather-compensated controllers. With this function, we greatly shorten the time in which the desired room temperature is reached, and therefore it is not necessary to change the setting of the desired room temperature or heating curve, which results in an undesired increase in room temperature towards the end of the daily room temperature interval.

Activate the “BOOST” function is and set the intensity of operation with parameters P2.3, while the operation time is set with the parameter P2.4. The same can be set using the parameters P3.3 and P3.4 “BOOST” for the second heating circuit. In most cases, it suffices that the desired temperature is increased by 3°C and the operating interval is set to 60 minutes. If the building has poor thermal insulation, a higher room temperature correction should be set, while in case of better isolation a smaller setting is sufficient.

We increase the operation interval for buildings with a greater time delay, e.g. in the case of floor heating. In this case, the controller increases the setting of the desired room temperature by 100% of the setpoint only if the night-time temperature interval was longer than 10 hours.

If the interval is shorter, the room temperature increase is reduced proportionally to 10% which is reached at 1h of the night-time temperature interval. If the night-time temperature interval is less than 1h, the “BOOST” function is not activated. The described operating mode provides another opportunity to fine-tune the operation of Seltron weather-compensated heating controllers. Due to accumulation and additional heat sources, the room temperature in the evening is usually slightly higher than the desired room temperature.

When we have a built-in room sensor, the latter only performs the stand-pipe temperature correction and ensures that the room temperature only minimally deviates from the desired setting. In the case where there is no room sensor a similar effect can be achieved by changing the time program. To do this, insert one or two shorter heating intervals with the night-time temperature in the evening program.

In this way, the desired reduction in room temperature is achieved. Take care that the night-time temperature interval is less than 60 minutes. Otherwise, the “BOOST” function will be activated to compensate for the reduction of room temperature without having the desired effect. The “BOOST” function can also be activated when a room sensor or room unit is connected. This comes in especially handy when the effect of the room sensor correction must be reduced or even switched off completely.

By installing an external sensor

Installation of the sensor into solar collectors

Temperature Sensor Instalation

Installation of the sensor into the solar sanitary water heater