A. A globe valve throttle at the boiler, a reducing valve, a steam gauge
connected to the steam heat pipe and the proper piping and hose
connections.

113. Q. What pressure is carried in the steam heat pipe, and how is it
controlled?

A. From twenty to sixty pounds in the train pipe, depending on the
length of the train, and is controlled by the regulating valve.

114. Q. What would you do in case the regulating valve failed to
operate?

A. In case the regulating valve would not admit sufficient steam to the
train pipe, would take it apart and block the steam valve open. If the
pressure ran up too high in the steam heat train pipe, would control it
with the steam throttle at the boiler head.

115. Q. How does the steam heat reducing valve control the pressure?

A. The inlet valve for live steam is opened and closed by the movement
of a metallic diaphragm in the valve which is opened by spring pressure
on one side and closed by steam pressure on the other side. To regulate
this pressure, stiffen the spring to carry more, weaken it to carry less
by turning the handle connected to this spring either up or down.

116. Q. If steam heat gauge showed the required pressure and cars were
not being heated properly, how would you proceed to locate the trouble?