Online Companions:

• Practical Heating Technology
  Author: Bill Johnson & Kevin Standiford
  ISBN 13: 9781418080396
  ISBN 10: 141808039X
• Refrigeration and Air Conditioning Technology, 5E
  Author: Bill Whitman; Bill Johnson; John Tomczyck
  ISBN 13: 9781401837655
  ISBN 10: 1401837654
• Residential Construction Academy: HVAC
  Author: Eugene Silberstein
  ISBN 13: 9781401849016
  ISBN 10: 1401849016