ASHRAE proposes cycling and thermostatic controls for unvented combustion devices

A new proposal has been approved by an ASHRAE working group, with assistance from the Vent-Free Alliance, that includes cycling, thermostatic controls, and information from the ASHRAE Position Document on Unvented Combustion Devices and Indoor Air Quality. It will be submitted to the Standing Standard Project Committee (SSPC) for consideration during their June meeting.
In March 2017, a proposal was submitted to ASHRAE SSPC 62.2, Ventilation and Acceptable Indoor Air Quality in Residential Buildings, that would have banned the installation of vent-free appliances in homes designated as 62.2 compliant. The proposal established criteria that was more stringent than the existing ASHRAE Position Document on Unvented Combustion and included an equation that used maximum input with no cycling provisions or consideration of temperature and human comfort.
Many comments were submitted during the proposal period and were not properly considered and resolved in accordance with ASHRAE procedures and ANSI Essential Requirements.
An official repeal and rejection period was established by the ASHRAE board of directors, and the Standards Committee established an ad hoc working group consisting of members, the SSPC, and the vent-free industry.
The result is the new proposal that includes cycling and thermostatic controls.