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Solar Approaches to Radiant Heating - Self Study


Author: Vaughan Woodruff

Subjects: Renewable HVAC: Hydronic Heating, Solar: Solar Thermal

Length: 6 modules

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14 students have taken this course


Professionals with relevant experience: learn the latest, most advanced concepts for integrating solar with radiant heating systems.

Learning Objectives

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Preview the Course Material

Check out a free preview of the course by clicking the button below. This is a live assignment from the course and will give you a good sense for what the course will be like.

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Learn from the Best

Vaughan Woodruff and the RPA are true leaders in solar and radiant design. This is an exciting opportunity to go into the minute details and learn from the best.

Valuable Tools

You'll receive Excel calculators and design tips that can be used on your next project.

Flexible Online Training for Industry Professionals

This is a self-study, self-paced online course. You can begin instantly upon enrollment and complete the course materials at your own pace.

Access Information and Build Your Training Library

After enrolling, the course materials will remain in your account and be accessible 12 months (1 year) after enrollment. Access can be extended beyond 1 year with a monthly membership. Rewatch videos and review assignments as many times as you want. View updates the instructor makes to the course as the industry advances. Return to your course anytime with online access from anywhere in the world.

Earn A Certificate of Completion

When you complete this course you are eligible for a certificate of completion from HeatSpring. You can download your certificate as soon as you have completed all of the course requirements. Students can easily share their verified certificates on their LinkedIn profiles using our LinkedIn integration.

Earn Continuing Education Credits

Approved for: 1 IAPMO CEUs, 1 RPA CEUs.


Vaughan Woodruff

Owner, Insource Renewables

Vaughan Woodruff owns Insource Renewables, a solar consulting firm in Pittsfield, ME. He is a NABCEP Certified Solar Heating Installer and serves on committees for NABCEP, IAPMO and IREC. Woodruff is a co-author of the NABCEP Solar Heating Installer Resource Guide and the author of NYSERDA’s Field Inspection Guidelines for Solar Heating Systems.

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Course Outline

Welcome - Orientation Materials

This is a self-study on demand course. This course is self-paced, so you don’t need to be logged in at any specific time. You can get started immediately after you enroll and the course materials will remain in your account with minimum guaranteed access for 12 months (1 year) after enrollment.

  • Introduction to HeatSpring (Video - 01:25 minutes) Preview
  • Meet Vaughan Woodruff, your course instructor, and learn more about the course (Video - 11:41 minutes) Preview
Module 1 - Applications of Solar & Radiant

The course begins with a discussion of solar (heating & PV) and radiant technologies, how they are complementary, advantages, and challenges of integrating them.

  • Introduction to Week 1 (Video - 01:21 minutes)
  • Solar Technology Tour (Video - 42:20 minutes) Preview
  • Applications of Solar & Radiant - An interview with Mark Eatherton of the Radiant Professionals Alliance (Video - 26:46 minutes)
  • > Required reading: Solar Heating and Cooling Applications (Download .pdf)
  • Integration Gone Bad, Part 1 (Video - 30:57 minutes)
  • Integration Gone Bad, Part 2 (Video - 23:39 minutes)
  • Integration Gone Bad, Part 3 (Video - 36:45 minutes) Preview
  • > Required reading: The Glitch & The Fix, "Seat of the Pants Solar" (Download .pdf)
  • > Exercise: Documenting System Errors (Download .pdf)
  • >> Beyond the course (optional): Well-Grounded Solar, A versatile way to integrate solar thermal and geothermal heat pumps (Download .pdf)
  • >> Beyond the course (optional): Solar District Heating (Resource)
Module 2 - System Types and Stagnation

This week we'll discuss the types of solar heating systems commonly used for solar combisystems and explore the overheating considerations that are unique to solar combisystems.

  • Introduction to Week 2 (Video - 03:16 minutes)
  • Antifreeze System Components & Operation (Video - 33:16 minutes)
  • Drainback System Components & Operation (Video - 21:23 minutes)
  • > Required reading: Caleffi idronics 6 - Solar Thermal Combisystems (p. 3-14; p. 23-26) (Download .pdf)
  • Stagnation Behavior (Video - 46:09 minutes)
  • Tutorial for Antifreeze Design Considerations Tool (Video - 34:07 minutes) Preview
  • > Spreadsheet: Antifreeze System Design Considerations (Download .xlsx)
  • > Required reading: Stagnation behavior in solar thermal systems (Download .pdf)
  • > Exercise: Evaluating System Conditions (Download .pdf)
  • >> Beyond the course (optional): COLLECTORS, SYSTEMS, AND APPLICATIONS (p. 18-44), from NABCEP Solar Heating Installer Resource Guide (Download .pdf)
  • >> Beyond the course (optional): Protecting Water Heating Systems with Expansion Tanks (Download .pdf)
  • >> Beyond the Course (optional): Heliodyne's PSP Method (by Heliodyne) (Download .pptx)
Module 3 - Techniques for Integrating Solar with Radiant

Beginning this week, we'll get into the details of solar storage strategies, and control considerations in solar combisystems. You'll learn some techniques to assist with system design for your project. This week spills into Week 4, where we will explore codes and standards related to these systems.

  • Introduction to Week 3 (Video - 03:25 minutes)
  • Integrating Solar and Radiant, a Conversation with John Siegenthaler, P.E., Appropriate Designs (Video - 39:31 minutes) Preview
  • Thermal Stratification (Video - 24:43 minutes)
  • > Required reading: CYLINDERS (p. 56-67), from Viessmann Technical Guide, Solar Thermal Systems (Download .pdf)
  • Tank-In-Tank (Video - 35:15 minutes)
  • >> Supplemental Resource (optional): Triangle Tube Smart Multi Energy Tank Installation Manual (Download .pdf)
  • Tank-in-Tank with Heating Lance (Video - 21:50 minutes)
  • >> Supplemental Resource (optional): Buderus Solar Design Guide (Download .pdf)
  • Immersed Coil with Sidearm Heat Exchanger (Video - 28:25 minutes)
  • >> Supplemental Resource (optional): Lochinvar Strato-Therm+ Installation & Operation Manual (Download .pdf)
  • Immersed Coil with Priority Loading (Video - 16:44 minutes)
  • >> Supplemental Resource (optional): SunMaxx StorMaxx CTEC Brochure (Download .pdf)
  • One-Tank Solution, Auxiliary Heat Integrated into Solar Storage (Video - 20:48 minutes)
  • >> Supplemental Resource (optional): HTP Versa Hydro Solar Supplement (Download .pdf)
  • Priority Loading with Separate Tanks (Video - 20:25 minutes)
  • Integrated Controls (Video - 14:40 minutes)
  • >> Supplemental Resource (optional): SolarLogic Integrated Control Users Manual (Download .pdf)
  • > Required reading: DRAINBACK SOLAR COMBISYSTEMS from Caleffi idronics, Vol. 6: Solar Thermal Combisystems (Download .pdf)
  • > Exercise: Configuring a Solar Controller for Priority Loading (Download .pdf)
  • > Recommended reading (optional): Storage Strategies (Download .pdf)
  • >> Beyond the course (optional): Caleffi idronics, Vol. 6: Solar Thermal Combisystems (Download .pdf)
  • >> Beyond the course (optional): Viessmann Technical Guide, Solar Thermal Systems (Download .pdf)
  • >> Beyond the course (optional): Modern Hydronic Heating by John Siegenthaler (Resource)
Module 4 - Code and Standards Considerations

This week we'll discuss codes and standards related to solar heating, including the USEHC, ASME requirements, ComibSol Best Practices, and other key design and installation requirements.

  • Introduction to Week 4 (Video - 02:27 minutes)
  • Codes and Standards, A Conversation with Les Nelson of IAPMO (Video - 29:57 minutes)
  • Solar Combisystem Codes and Standards (Video - 33:24 minutes)
  • Legionella (Video - 18:59 minutes)
  • > Required reading: CombiSol Project, Criteria for Best Practice (Download .pdf)
  • > Required reading: Code Considerations in Solar Water Heating Systems (Download .pdf)
  • > Required reading: Standardizing Solar Combisystems (Download .pdf)
  • Solar Combisystem Codes and Standards (Quiz)
  • > Recommended reading (optional): CombiSol Project, State of the Art Report on Solar Combisystems (Download .pdf)
  • > Recommended reading (optional): Legionella in Combisystem Tanks (Download .pdf)
Module 5 - Combisystem Economics

In the sales process, prospective clients will often inquire about the benefits of a solar heating system. Analyzing system production when integrating solar with a radiant system requires understanding of building science and solar modeling programs. This week, we will analyze the information needed to model these systems and examine how to use the results of these models to support the sales process.

  • Introduction to Week 5 (Video - 04:15 minutes)
  • Selling Solar Combisystems, a conversation with Claudia Pavel of SolarLogic, LLC (Video - 36:34 minutes)
  • Modeling Solar Combisystems (Video - 40:08 minutes)
  • >> Resource: Sample Combisystem Modeling Output (Download .pdf)
  • > Required reading: How to Perform a Heat-Loss Calculation, Part 1 (Resource)
  • > Required reading: How to Perform a Heat-Loss Calculation, Part 2 (Resource)
  • >> Resource: 2012 International Plumbing Code, Appendix D - Degree Days and Design Temperatures (Resource)
  • >> Resource: Manual J Residential Load Calculation - Outdoor Design Conditions (Resource)
  • System Payback (Video - 33:44 minutes)
  • >> Resource: Database of State Incentives for Renewables & Efficiency (Resource)
  • >> Resource: EIA's Heating Fuel Comparison Calculator (Download .xls)
  • > Exercise: Determining System Payback (Download .pdf)
  • > Recommended reading (optional): Annual Efficiency Calculation for Condensing Boilers (Download .pdf)
Module 6 - Capstone Project

To finish out the course, you're going to design a full system, including drawings, calculations, and equipment selection. You'll walkaway with the confidence to do these designs on your client projects.

  • System Sizing (Video - 34:47 minutes)
  • > Capstone Project: Solar Combisystem Design (Download .pdf)
Feedback and Additional Resources

This is our last module but you still have access to the all of course materials for 12 months (1 year), so keep working and you'll be able to complete the course at your own pace. After your year of access expires you can optionally extend access with a HeatSpring Membership. Enjoy the course and keep in touch!

  • 1 Year of Access to Course Materials (Text)
  • Feedback: 2-minute Exit Survey (Survey)
  • Consider Joining as a HeatSpring Member (Resource)
  • Certificate of Completion: Request a Certificate (Certificate)
Free Preview - Meet Vaughan Woodruff, your course instructor, and learn more about the...

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