The Federation of Synagogues has warned that several leading brands of oven are unsuitable for Shabbat and festival use because of a new safety feature. 

Bosch, NEFF and Siemens electronic ovens now automatically switch off their heating elements when the oven door is opened. Therefore, anyone opening the door would breach the prohibition against turning electricity on or off. 

BSH Home Appliances Limited, which manufactures the brands, has apologised and advised affected customers to contact them. 

A number of ovens come fitted with a “Sabbath mode” function which, for example, would stop the oven light or fan coming on or off when the door is opened. Some allow an oven to remain on low temperature for up to 72 hours over Yomtov when it would normally automatically cut off after a certain time. 

But the Federation’s Fedtech department advises the use of only models with rabbinic approval.

BSH said it began implementing the change last May after the International Safety Standard was updated in light of “the increasing number of WiFi-enabled products on the market which offer remote operation”. Ovens were now required to automatically switch off heating elements when the door was opened.

"If the oven door is now opened while in Sabbath function, all heating elements are now switched off until the door closes again," BSH explained.

"This means that our Bosch, NEFF and Siemens electronic ovens no longer meet the basic needs for use during the Sabbath and Yomtov, as the status of the oven changes when the door is opened."

The company understood "the importance of following the Sabbath and would like to offer our sincere  apologies. This change was made with safety at the forefront and we can only apologise that this has now compromised the Sabbath function.” 

Both BSH and Fedtech said they were “working closely” to find a solution. 

Fedtech director Rabbi Yisroel Moshe Guttentag said the problem first came to light a few months ago. Customers with the updated ovens may not have initially realised the oven was turning off because the heating elements might still be glowing. 

“We have fielded a tremendous volume of calls from people who have the ovens."

He said it would not be practical to use the ovens on Yomtov. But on Shabbat, it would be possible to wire a timeswitch into the oven socket and set it to turn the oven off before the door was opened. 

BSH advised customers to make inquiries by email COG-sabbathenquiry@bshg.com