boiler room 
noun
1A room in a building or a compartment in a ship containing a boiler and related heating equipment.The apartment includes a sitting room, study, kitchen, utility, boiler room, two bedrooms, bathroom and separate toilet....
- Then on the Friday before the children were due to return to school in January, the heating system pump burst, leaving the boiler room underwater and the main school building with no heating once more.
- The wheel was put hard over, causing the first torpedo to miss, but the second struck the forward boiler room, splitting the ship in two and causing her to sink within 15 seconds.
2A room or office in which many operators engage in high-pressure telephone sales, especially of risky or worthless investments: [as modifier]: a boiler-room operation...
- The authors depicted a high-pressure sales culture that resembled a telemarketing boiler room more than a university admissions office.
- He is by far the best salesman in his boiler room.
- Remember that boiler-room operators are well-versed in making you feel utterly inadequate by your lack of knowledge about a particular company or ‘ground-breaking’ product.