Control should be considered in two areas;

	Room control – controlling the temperature in the individual rooms usually by the use of a room thermostat or sensor
	Water control � varying the supply water temperature as a function of the outside air temperature, is an effective way of controlling the heat output from the floor heating and cooling system, ensuring that only the minimum energy required is transferred into the floor mass

Room control systems
velta provide a complete range of room control systems;

	veltamat standard – 230v or 24v – standard control system providing individual room temperature control
	veltamat programmable – 230v or 24v – with time programming and set back facility
	veltamat KRD variable control – fully modulating programmable system with set back and low voltage 12v DAC
	velta genius radio controlled wireless system – fully programmable system designed for use with floor heating to measure radiant heat. (with vivaldi control card capable of providing control for heating and cooling)

Water control and weather compensation
The heat losses from a building are mainly a function of the building fabric and the external weather conditions. It is therefore logical that the energy required to heat a building will vary in line with external conditions.

Weather compensation is essential for a floor heating system and is achieved by constantly modulating the temperature of the water flowing within the floor to ensure that only the correct amount of energy is transferred into the thermal mass of the floor. Too much available energy stored in the floor may lead to areas overheating even though room controls have stopped the flow of water within the floor. Well designed weather compensation leads to good self-regulation of the system.

 
velta regulating stations provide this control in fully fabricated units ranging from 7kW through to 50kW units, incorporating modulating pumps, motorised mixing valves, dual water sensors, internal and external sensors, safety cut outs and fully programmable veltamat 3D microprocessor controller.

The veltamat 3D controller can be programmed for use with all the velta systems and provides optimum start facililty, safety cut out, maintenance cycling, valve control, pump control utilising specifically designed software and microprocessor technology.

	RS2 unit for regulation of small areas with loads of up to 2kW
	ERS regulators for single manifold applications up to 15kW
	ZRS regulators for multiple manifold applications 10-25kW
	SH-RS regulator for larger applications 25-50kW
	FH-KM regulators for use with heat exchangers 15-30kW
	veltamat 3D control regulators

Modern floor heating systems generally operate with floor temperatures of 22°� 23°C (2-3°C above the required room temperature of 20°C) and the heat output from the floor changes instantly as the room or floor temperature changes.

The greater the differential is between the floor temperature and the room air temperature, the greater the output available from the floor. The closer they are to each other the lower the output.

If the room reaches the same temperature as the floor then the floor cannot pass heat into the room and is neutral. Should the room temperature rise above the floor temperature then heat will pass from the room to the floor! A cooling system. This effect of self-regulation is a major advantage of floor heating and cooling systems, which is not found in most other forms of heating methods.