Controlling under surface heating/cooling

Abstract

The invention relates to controlling an under surface heating / cooling. During a heating mode, the room temperature is increased by increasing the flow of the liquid in a supply loop (3). If the set point has an increase that is greater than a pre-determined value, the supply temperature of the liquid is increased. During a cooling mode, the room temperature is decreased by increasing the flow of the liquid in the supply loop (3). Correspondingly, in response to a set-point change greater than a pre-determined value, the supply temperature of the liquid is temporarily decreased.

Description

BACKGROUND OF THE INVENTION[0001]The invention relates to a method of controlling an under surface heating in which a room is heated using a supply loop in which liquid is circulated for heating the room, the method comprising increasing room temperature by increasing the flow of the liquid in the supply loop.[0002]The invention further relates to a method of controlling an under surface cooling in which room is cooled using a supply loop in which liquid is circulated for cooling the room, the method comprising decreasing room temperature by increasing the flow of the liquid in the supply loop.[0003]Yet further the invention relates to a hydronic heating / cooling system comprising a main supply pipe, a main return pipe, at least one supply manifold, at least one return manifold, heating loops from the supply manifold to the return manifold, actuators for controlling the flow in the heating loops arranged to the supply manifold and / or the return manifold and a control unit comprising ...

AI Technical Summary

Benefits of technology

[0014]In the invention, during a heating mode, room temperature is increased by increasing the flow of the liquid in a supply loop. If the set point has an increase that is greater than a pre-determined value, the supply temperature of the liquid is increased. Thus, a boost mode is activated for raising the temperature. This provides the advantage that the step response of the room temperature is faster, i.e., the room temperature is raised faster. By reducing the heat-up time, energy is saved, because the average room temperature could be decreased by fast transitions when increasing the temperature. The solution also provides improved comfort.

[0015]In an embodiment, the zones with the latest set-point changes are prioritized by the controller for a period of time or until the set points are reached. This further speeds up the raising of the temperature in these zones whereby the heating of the other parts is not essentially disturbed.

[0016]In another embodiment, cold liquid is supplied to the loop in the last stage before reaching the new set point. This feature reduces or minimizes the overshoot and the heating ramp can also be steep close to the set point. Thus, the heating time can be reduced and overshoot minimized.

[0017]In a yet another embodiment, previous transitions and outside temperatures are analyzed and the transition ramps are optimized on the basis of the analysis. This feature further increases the speed of the transition and reduces overshoot.

Problems solved by technology

An under floor heating system is quite a slow system.

Thus, typically quite a long time, for example several hours, is needed to raise the temperature from the lower value to a comfort temperature.

However, this kind of compensation is extremely complicated for transitions between different temperatures.

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