Install Instructions

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IM-PR 566442 1114 (Design Manual)

Secondary Piping: Piping that is either directly

connected to primary piping or originates off

manifolds fed by primary piping, but is not located

within a radiant emitter.

Series Piping: Piping that connects manifolds or

radiant emitters from end-to-end, creating one

continuous loop.

Snow-Free Area Ratio (Ar): The ratio of the

surface area where no accumulation takes place

during snowfall versus the total area of the surface.

Snow-Melt Confidence Level: The percent of

the hours of snowfall during a typical year that the

snow-free area ratio is maintained.

U-Value: U-value (or U-factor) is a measure of

the rate of heat loss or gain through a construction

of materials. The lower the U-factor, the greater

the material’s resistance to heat flow and the

better the insulating value. U-value is the

inverse of R-value.

Variable Flow Rate: Occurs when a circulator

operates at multiple speed settings.

Variable Temperature Setting: Occurs when

a radiant heating or cooling source’s supply

temperature is delivered at multiple settings.

Zone: An area of a building for which space

conditioning is controlled by a single thermostat.