1.1 General
This Standard specifies performance requirements for thermostats (120 to 240 V) intended for switching of a controlled resistive heating load.
The models covered by this Standard are as follows:
a) wall-mounted thermostats used with baseboards, panel convectors, or radiant floors;
b) built-in thermostats (1000 W up to 1500 W) used in baseboards or panel convectors; and c) two-component thermostats.
1.2 Thermostats not covered by this Standard
Thermostats used exclusively or built-in in the following units are excluded:
a) fan-forced heaters;
b) kick space;
c) fireplaces;
d) thermal storage heaters;
e) electric baseboards and convectors incorporating both convection and radiant heating elements;
f) portable heaters; and
g) central heating units under the control of a single thermostat.
1.3 Thermal regulation and power grid issues
The mandatory part of this Standard specifies performance requirements covering thermal regulation. The thermal regulation requirements are based on testing in a dual-climate test chamber. Informative Annex C outlines
a) proposed limits on the level of some types of emissions that might be generated by thermostats; and
b) grid impacts that thermostats may help alleviate.
1.4 Terminology
In this Standard, “shall” is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the standard; “should” is used to express a recommendation or that which is advised but 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 text 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.
1.5 Units of measurement
The values given in SI (metric) units are the standard. The values given in parentheses are for information only.