A special gathering was held in the home of HaRav Berel Povarsky of the Mishmeres Shabbos with the CEO of the company Chashmal Hakeren Dovid Segal. The main topic of discussion was the issues with using inverter air conditioners on Shabbos.
The conference was attended by revered rabbonim: HaRav Shevach Tzvi Rosenblatt, rabbi of Bnei Brak; HaRav Binyomin Garbus, dayan in the Bnei Brak Beis Din and Moreh Tzedek by HaRav Moshe Shaul Klein, and HaRav Eliyahu Beifus, Rav and Chairman of the Mishmeres HaShabbos organization.
The inverter is able to adjust the flow of electric current on a continuous basis, based on the feedback it receives on the conditions in the space. It is very sensitive even to small changes.
In general, the power of the current determines the power of the cooling. The rating of the unit is the amount of cooling it can deliver. In a conventional unit, the compressor is either on or off, meaning that it will either deliver its maximal cooling power or nothing.
The inverter can adjust the power it delivers according to the needs of the environment. Some manufacturers say that the an inverter unit can be turned on at the beginning of the season and not turned off until the end. It will continually adjust itself optimally to conditions and in the end it will use less electricity than a conventional unit even if it runs continually.
All modern air conditioners have temperature sensors that can distinguish even small changes such as a tenth of a degree. However conventional air conditioners only react to much larger changes.
The inverter, on the other hand, is sensitive to lesser changes and it can make even small adjustments, which is why it is difficult to know which degree of heat will affect it. And here is where we meet the halachic problem. Since the device is constantly monitoring its vicinity and will respond unpredictably, it has been prohibited by the major poskim for Shabbos usage unless it has a special Shabbos mode.
HaRav Beifus said that Rabbi David Segal is the pioneer of air conditioners and was instrumental in having all the companies install mehadrin Shabbos controls. "In this merit, many companies have recognized Shabbos control devices even for regular air conditioners which do not really require the device but only as a hiddur. But since this has become an option, many have begun to choose the preferred option so that a special Shabbos device has been developed for the Inverter air conditioners.
HaRav Berel Povarsky said, "The holy Shabbos is deserving to lay out money for its observance; it is the source of all blessing."
He blessed the Mishmeres HaShabbos for this holy work, as well as HaRav David Segal, chairman of "Chashmal Hakeren," which supervises to the finest detail all of the products so that they comply lechatchila for Shabbos usage.
In the course of the meeting, a message from the late HaRav Chaim Kanievsky zt"l was read which stated that it is clear that a person must buy an air conditioner with a Shabbos Device. In his words, "He will surely be rewarded for his Shabbos observance."
HaRav Povarsky was asked if it could be publicized in his name that one should insist on the Mishmeres HaShabbos device in purchasing air conditioning.
He answered. "First, one must be vigilant not only in buying a new air conditioning system but also to make sure that an existing one adheres to the parameters of the Mishmeres HaShabbos. This is not an extra stringency or preferred option but an absolute obligation so as not to transgress the laws of Shabbos. Shabbos is surely worthy enough to warrant its full observance."
