8 Low pressure heaters
The current generation of surface type U-tube low pressure (LP) heaters has developed from the traditional surface LP heater, which has been in use for the last 70 years.
The design has been updated to take advantage of modern manufacturing techniques and materials. The latest designs of heaters are also constructed to take full advantage of a horizontal attitude.
The other design of LP heater currently in use on the 500 MW units and the early 660 MW units is the direct contact type. They are similar in design and construction to the de-aerating head of a de-aerator.