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.

1 . 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, and   in response to a set-point change greater than a pre-determined value, increasing temporarily the supply temperature of the liquid.   
     
     
         2 . A method according to  claim 1 , comprising prioritizing by a controller zones with latest set-point changes for a period of time or until the set points are reached. 
     
     
         3 . A method according to  claim 1 , comprising supplying cooler liquid to the loop before reaching the set point for reducing overshoot. 
     
     
         4 . A method according to  claim 3 , wherein the cooler liquid is obtained by opening temporarily at least some of the actuators of other loops. 
     
     
         5 . A method according to  claim 1 , comprising analyzing previous transitions and outside temperatures and optimizing transition ramps on the basis of the analysis. 
     
     
         6 . A method according to  claim 1 , comprising controlling the flow of the liquid on and off such that during a duty cycle the flow is high and between the duty cycles the flow is off, whereby room temperature is controlled by controlling the percentage of the duty cycles. 
     
     
         7 . A method of controlling an under surface cooling in which a 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, and   in response to a set-point change greater than a pre-determined value, decreasing temporarily the supply temperature of the liquid.   
     
     
         8 . A method according to  claim 7 , comprising supplying warmer liquid to the loop before reaching the set point for reducing overshoot. 
     
     
         9 . 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 including means for controlling the actuators for controlling the flow of the liquid in the supply loop, means for temporarily increasing the supply temperature of the liquid in heating mode and/or means for temporarily decreasing the supply temperature of the liquid in cooling mode in response to a set-point change greater than a pre-determined value. 
     
     
         10 . A system according to  claim 9 , wherein the control unit comprises means for controlling cooler liquid to be supplied to the loop before reaching the set point in heating mode and/or for controlling warmer liquid to be supplied to the loop before reaching set point in cooling mode for reducing overshoot. 
     
     
         11 . A system according  claim 9 , wherein that the actuators are arranged to control the flow in the heating loops on and off such that during the duty cycle the flow is high and between the duty cycles the flow is off. 
     
     
         12 . A software product of a control system of a hydronic heating system in which liquid is led along a main pipe to supply manifold and distributed in the manifold into heating loops, the heating loops returning a return manifold, at least one of the manifolds having actuators for controlling the flow in the heating loops, wherein
 the execution of the software product on a control unit of the control system is arranged to provide the following operations of   increasing room temperature by increasing the flow of the liquid in the supply loop and,   in response to a set-point change greater than a pre-determined value increasing temporarily the supply temperature of the liquid.   
     
     
         13 . A software product of a control system of a hydronic cooling system in which liquid is led along a main pipe to a supply manifold and distributed in the manifold into heating loops, the heating loops returning to a return manifold, and at least one of the manifolds having actuators for controlling the flow in the heating loops, wherein
 the execution of the software product on a control unit of the control system is arranged to provide the following operations of   decreasing room temperature by increasing the flow of the liquid in the supply loop and   
       in response to a set-point change greater than a pre-determined value decreasing temporarily the supply temperature of the liquid. 
     
     
         14 . A method according to  claim 2 , comprising supplying cooler liquid to the loop before reaching the set point for reducing overshoot. 
     
     
         15 . A system according  claim 10 , wherein that the actuators are arranged to control the flow in the heating loops on and off such that during the duty cycle the flow is high and between the duty cycles the flow is off.