ASHRAE-90.1-2022- - Page 027
Extracted Content
radiant heating system: a heating system that transfers heat to objects and surfaces within the heated space primarily (greater than 50%) by infrared radiation.
rated motor power: see motor power, rated .
rated R-value of insulation: the thermal resistance of the insulation alone as specified by the manufacturer in units of h·ft [2] ·°F/Btu at a mean temperature of 75°F. Rated R-value refers to the thermal resistance of the added insulation in framing cavities or insulated sheathing only and does not include the thermal resistance of other building materials or air films. (See thermal resistance .)
rating authority: the organization or agency that adopts or sanctions use of Normative Appendix G when quantifying performance that exceeds requirements of this standard.
readily accessible: installed in a manner and location that allows it to be reached quickly for operation, renewal, or inspection without requiring those to whom ready access is requisite to climb over or remove obstacles or to resort to portable ladders, chairs, etc. In public facilities, accessibility may be limited to certified personnel through locking covers or by placing equipment in locked rooms.
recirculating system: a domestic or service hot-water distribution system that includes a closed circulation circuit designed to maintain usage temperatures in hot-water pipes near terminal devices (e.g., lavatory faucets, shower heads) in order to reduce the time required to obtain hot water when the terminal device valve is opened. The motive force for circulation is either natural (due to water density variations with temperature) or mechanical (recirculation pump ).
recool: to lower the temperature of air that has been previously heated by a mechanical heating system .
record documents: drawings and other documents that record the conditions of the project as constructed. These include any refinements of the construction documents or bid documents.
refrigeration system, low-temperature: system for maintaining food products in their frozen state in refrigeration applications.
refrigeration system, medium-temperature: system for maintaining food products above their frozen state in refrigeration applications.
refrigerant dew point: the refrigerant vapor saturation temperature at a specified pressure.
regulated energy use: energy used by building systems and components with requirements prescribed in Sections 5 through 10. This includes energy used for HVAC, lighting, service water heating, motors, trans- formers, vertical transportation, refrigeration equipment, computer-room cooling equipment, and other building systems, components, and processes with requirements prescribed in Sections 5 through 10.
reheat: to raise the temperature of air that has been previously cooled either by mechanical refrigeration or an economizer system .
renewable energy resources: energy from solar, wind, biomass or hydro, or extracted from hot fluid or steam heated within the earth.
repair: the reconstruction or renewal of any part of an existing building for the purpose of its maintenance.
replacement air: outdoor air that is used to replace air removed from a building through an exhaust system . Replacement air may be derived from one or more of the following: makeup air, supply air, and transfer air .
reset: automatic adjustment of the controller set point to a higher or lower value.
residential: spaces in building s used primarily for living and sleeping. Residential spaces include, but are not limited to, dwelling units, hotel/motel guest rooms, dormitories, nursing homes, patient rooms in hospitals, lodging houses, fraternity/sorority houses, hostels, prisons, and fire stations.
residential associated HVAC zone: any HVAC zone that primarily includes nonresidential spaces designed to serve occupants of residential spaces, including but not limited to corridors, stairwells, elevator lobbies, and common restrooms, on a floor where over 75% of the gross conditioned floor area are residential spaces . This definition does not apply to HVAC zones within hospitals.
resistance, electric: the property of an electric circuit or of any object used as part of an electric circuit that determines for a given circuit the rate at which electric energy is converted into heat or radiant energy and that has a value such that the product of the resistance and the square of the current gives the rate of conversion of energy .
ANSI/ASHRAE/IES Standard 90.1-2022 (I-P) 25