This standard is based, to a large extent, upon ANSI/ ASHRAE Standard 94-77, "Methods of Testing Thermal Storage Devices Based on Thermal Performance." Originally it had been planned to publish Standard 94.2 as an additional section to Standard 94-77. As the Standard Project Committee's work progressed, however, it became apparent that the differences between the two standards would be larger than had been originally assumed. In order to facilitate the use of the standard, it was therefore decided to issue it as a separate document.

There are essentially two types of heat storage devices in existence that can be tested by this standard: central devices and room devices. Central devices are located at a central location from which their output is ducted or piped to the point of use or to a heat exchanger. Room devices are installed within the space to be heated; they are sometimes referred to as radiator devices because they release their heat by either radiation or convection or a combination of the two. Separate testing procedures are prescribed for the two types of storage device.

Numerous provisions in this standard are identical to those of Standard 94-77, particularly Sections 4 and 5 and Subsections 6.1 through 6.5. Figures 2 and 4 were also taken from that standard without change; other figures were used with minor changes.

The financial contribution of the U.S. Department of Energy, which paid for the travel expenses of some of the Project Committee members in order to accelerate the preparation of this standard, is gratefully acknowledged.

Units: Dual