National Oilheat Research Alliance 3
Introduction
Take a moment to think about the flowing
three statements:
• The components of warm air systems control
the flow of air.
• The components of hot water systems control
the flow of water.
• The components of steam systems control
the flow of steam.
They each make sense, right? The sound like
“no brainers,” don’t they?
But are they accurate?
In the case of steam heat the statement is, at
best, incomplete. For a steam system to operate
properly, the components must control the flow
of steam, water and air.
Of course, the components control the flow
of steam to the heat emitters, but as that steam
moves through the piping two things need to
happen:
1.Air must be pushed out of the way and
eliminated from the system.
2. As the steam condenses and becomes
water it has to be captured and returned to the
boiler.
Then, after the unit shuts off, air must be
pulled back in to the system.
If the movement of the steam, water or air is
interrupted the system will not operate properly.
In this publication you’ll learn about the
various types of steam heating systems; the
components of steam heating systems and how
each affects system performance; the proper
piping of steam systems; troubleshooting tips
and other information that will help you to
understand and service your customer’s steam
heating systems.
The following publications are recommended
for those who wish to learn more about steam
heating systems:
• Residential Hydronic Heating Installation
& Design (I=B=R) Guide RHH, available from
the Air Conditioning and Refrigeration Institute,
www.acca.org/store
• Any (or all) of Dan Holohan’s books on
steam, especially the “Lost Art’ series, available
at www.heatinghelp.com/store/