Possible Clues:

• Gang in heathlands climbing misty location
• Same motor working in place generating heat?
• Turkish bath chamber
• Sauna alternative
• Vapour bath — more atoms (anag)
• Othello's backside clenched that's hot and sweaty
• It'll make you sweat
• Spa feature
• Master flayed low back in sauna
• Place for a sweater?