Preface
This is the third edition of ANSI Z21.74 Standard for Portable refrigerators for use with HD-5 propane gas. It supersedes the previous editions published in 1992 and 1983.
Scope
1.1
This Standard covers gas-fired refrigerators, hereinafter referred to as refrigerators or appliances, having refrigerated spaces for:
a) storage of foods; or
b) storage of foods and making ice; or
c) storage of frozen foods and making ice; or
d) storage of foods and the storage of frozen foods and making ice.
This Standard applies to newly produced, unvented, portable refrigerators constructed entirely of new, unused parts and materials, with input ratings of 1000 Btu per hour (293 W) or less, and which are for use with HD-5 propane gas only. These refrigerators are intended for use both indoors in adequately ventilated structures and outdoors.
1.2
This Standard applies to refrigerators designed for self-contained fuel supplies and using fuel cylinders of not more than 75 cubic inches (1230 cm3) (21/2 pounds nominal water capacity). Fuel supplies shall be in accordance with the Standard for the Storage and Handling of Liquefied Petroleum Gases, NFPA No. 58.
1.3
Refrigerators submitted for examination under this Standard shall use Group 2 refrigerants in quantities not exceeding 6 lb (2.7 kg). Group 2 refrigerants include, but are not limited to, the following:
Refrigerant ANSI/ASHRAE 34 Designation
Ammonia (NH3) 717
Refrigerant systems shall comply with the applicable provisions of the Standard Safety Code for Mechanical Refrigeration, ASHRAE 15.
1.4
A refrigerator submitted for examination under this Standard shall be provided with a direct self-contained type of system employing the absorption or adsorption principle of refrigeration.
1.5 This Standard also covers all electrical equipment, wiring and accessories built in or supplied with refrigerators for use with low voltage direct current or alternating current. Appliances for use with alternating current shall be nominally rated 120 volts, 60 hertz.
1.6
Refrigerators for use with gas fuel that are also for use with electricity shall also comply with the applicable provisions of the Standard for Household Refrigerators and Freezers, UL 250.
1.7
If a value for measurement as given in this standard is followed by an equivalent value in other units, the first stated value is to be regarded as the specification.
1.8
All references to psi throughout this standard are to be considered gauge pressures unless otherwise specified.
1.9
This Standard contains SI (Metric) corresponding to the yard/pound quantities, the purpose being to allow the standard to be used in SI (Metric) units. (Standard for use of the International System of Units (SI): The Modern Metric System, IEEE/ASTM SI I0 or ISO 80000-1:2009 Quantities and units - Part 1: General are used as a guide in making metric conversion from yard/pound quantities.) If a value for a measurement and a corresponding value in other units are stated, the first stated value is to be regarded as the requirement. The given corresponding value may be approximate. If a value for a measurement and a corresponding value in other units are both specified as a quoted marking requirement, the first stated unit, or both shall be provided.
1.10
In this Standard shall is used to express a requirement, i.e, a provision that the user shall satisfy in order to comply with the standard; should is used to express a recommendation or that which is advised by not required; and may is used to express an option or that which is permissible within the limits of the standard.
Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the test explanatory or informative material.
Notes to tables and figures are considered part of the table or figure and may be written as requirements.
Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.
