Glossary

BTU, British Thermal Unit:

The amount of heat required to raise the temperature of one pound of water, one degree Farenheit.The standard unit of heat.

Convection:

Heat carried by the movement of gas or liquid. Warm air is less dense than cold air and therefore rises. Radiators, despite their name use convection currents of warm air to carry heat around the room.

kWH:

Killowatt hours. Electrical term - 1 Kwh equals the use of 1000 watts for one hour.

Manifold

The Manifold is the central point of the UFH system, from which warm water is pumped out to the floors. Usually will have servo-motor valves to open ports on signal from a thermostat & may come equipped with flow meters & mixing valve for some applications.There will be at least 1 manifold for each floor. Multiple manifolds are more common with moremodern short loop systems.

Pipe is normally laid in an unbroken loop to & from the manfold so that there are \no pipe unions under the floor.See also "manifold" on System page.

Radiant Heat:

Heat travelling in its most direct form of "infra-red" energy.

zone/zone control:

Zone is an area controlled by a thermostat which can turn on the heat source if required or signal to turnoff if it no longer requires heat. Full zone control demands each area be piped independently & have a thermostat connected to at the very least a di-polar relay for pump/heat source switching.