As you may have noticed, above you will find words for "An automatic non-return valve that opens when the boiler is at less than atmospheric pressure so as to avoid any risk of vacuum collapse when a hot boiler is allowed to cool down out of service.". Hover the mouse over the word you'd like to know more about to view its definition. Click to find a better fitting word. Finally, thanks to ChatGPT, the overall results have been greatly improved.