Solar Water Heating--Revised & Expanded Edition : a Comprehensive Guide to Solar Water and Space Heating Systems

258 Pages·2010·101.58 MB·English

by  Bob Ramlow, Benjamin Nusz

Advance Praise for
Solar Water Heating
Solar Water Heating answers the what? why? and how? of solar thermal
water heating system design and installation. Employing down·to ·earth language
and clear illustrations, this book succeeds in demystifYing solar thermal in a way
no other book has done. I take great pleasure in recommending this book to
everyone I can. Information is power and this book is loaded with it.
- MIKE HELFMAN, president, Bubbling Springs Solar
Bob's book will be required reading for all of our new installation personnel
since it provides a complete and comprehensive history, guide and information
about the type of work we do every day. It is nice for our new people to get a solid
overview of the many types of technologies and strategies for using solar hot water.
- RICHARD LANE, Managing Partner, Solar Mining Company
Bob Ramlow's Solar Water Heating is a practical solar encyclopedia for
anyone interested in instaLling a solar energy system or in starting a solar energy
company. The folksy writing is clear and the numerous diagrams make this book a
great resource for everyone from the novice just getting started to the existing solar
professional looking to pick up some of Bob Ramlow's many useful observations
from a long career installing and maintaining solar energy systems.
- DON WICHERT, Director, Renewable Energy Programs,
Wisconsin Energy Conservation Corporation
It's high time someone wrote a comprehensive but accessible overview of
solar heating, which is one of the most cost· effective steps that we can take to
wean from fossil fuels. Bob Ramlow is a rare combination of plumber, engineer, and
public educator who has learned with his own hands. Whether you wish to do it
yourself or simply be an informed consumer, start with SolarWater Heating!
- WINDY DANKOFF, solar industry pioneer and educator since 1975,
and founder of Dankoff Solar Products
LAR
WATER HEATING
A COMPREHENSIVE GUIDE TO
SOLAR WATER AND SPACE HEAnNG SYSTEMS
REVISED 8r EXPANDED EDITION
BOB RAMLOW and BENJAMIN NUSZ
{~\
~
NEW SOCIETY PUBLISHERS
Copyright © 2010 by Bob Ramlow and Benjamin Nusz. All rights reserved.
Cover design by Diane McIntosh.
Cover photo © Edward Caldwell. Al l rights reserved.
Interior illustrations by Benjamin Nusz, unJ ess otherwise indicated.
Printed in Canada by Friesens. First printing April 2010.
Paperback ISBN: 978-0-86571 -668- 1
Inquiries regarding requests to rep rin t all or pan of Solar Water Heatillg should
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Library and Archives Canada Cataloguing in Publication
Ramlow, Bob
Solar water heating: a comprehensive guide to solar water and space heating systems / Bob
Ramlow and Benjamin Nusz. - Rev. and expanded ed.
Includes index.
ISBN 978 -0-86571-668-1
1. Solar water heaters. 2. Solar space heating. 3. Solar heating. 4. Solar collectors. 1. Nusz,
Benjamin II. Tide.
TH7413.R342010 697 '.78 C2 010-902533 -4
t~4~~1
Mixed Sources
J;j
~ Cert no. sW·COC·OO1271
C 1996 F5C
NEW SOCIETY PUBLISHERS FSC
CONTENTS
Acknowledgments ......... ..... ..... ............................... ......... ..... ..... .......................... IX
Introduction ....................................................................................................... 1
Chapter 1: History .......................................................................................... 5
Chapter 2: Conservation and the Economics of Solar Water Heating ........ 11
The True Cost of Fossil Fuel ......................................................... 13
A Brief History of Fossi l Fuels .......................... ..................... ........ l5
Life-Cycle Costing ........................ .. ... .... ....................................... 17
Chapter 3: Types of Solar Collectors ..................... .. ........ .. ... .. .... .......... ........ 23
Flat Plate Collectors ......................................................... ..... ........ 24
Evacuated Tube Collectors ..................... .. ........ .. ... .. .... .......... ........ 26
ICS Collectors .............................. ......... ........ .. .. ... .. .... .......... ........ 30
Concentrating Collectors ............................................................. 32
Pool Collectors .................................................................... ........ 33
Comparing Solar Water Heating Collectors ...... .. ... .. .... .......... ........ 34
Air Collectors .................................................................. .. ... ........ 39
Chapter 4: Other System Components ................. .. ... .. ... .. ... .. .... .......... ........ 41
Storage Tanks ....................................... .. ............................. ....... .41
Heat Exchangers ............ .. ......... ..... ..... ............. .. .... .... .................. .46
v
VI I SOLAR WATER H EATI NG
Pumps .................................................................... ..... ...... ......... .47
Piping and Pipe Insulation ........................ .. ... .. ........ ... ... .. ... ...... .... 49
Solar Fluids .................................................................................. 51
Other System Components ............ ..................... ..... .. ... .. ... .. ....... .53
Chapter 5: Solar Water Heating Systems ....................... .. ............................. 65
Introduction ......................... ... ... .... .................... ....... ..... ..... ......... 65
Pressurized Antifreeze Systems ........................ ... ........ ..... ..... ......... 68
Drainback Systems .............................................. .......................... 77
Integral Collector Storage Systems ............................................... 82
Thermosiphon Systems .................................. ..... ............... .. ......... 84
Open ·Loop Systems ...................................................................... 86
Draindown Systems.. ........................................... .... ...... ..... .. .. ....... 87
Refrigerant Solar Water Heaters .......... .. ... ... .. .. ... .. ......................... 89
Solar Heated Pools ............................... .. ........ .................... .. ......... 90
Solar Heated Hot Tubs and Spas .................... ..... ......... .. ............... 94
Chapter 6: Solar Space Heating Systems ............................ .. .... ..... .. .. .. ......... 97
Liquid-Type Solar Heating Systems ...................... .. .. ...... ..... .......... 99
Liquid-Type Systems without Storage ........................................... 99
Liquid-Type Systems with Storage ............................................... 101
Heat Delivery Methods ........................................ ....................... 11 0
High·Mass Systems ......................... .. ... .. .................... .... .. ........... 119
Air-Type Solar Heating Systems ................................ .. ................ 124
Chapter 7: Choosing the Right System for Your Needs ............................ 129
Siting a Solar Energy System ....................................................... 130
Sizing a Solar Water Heating System ........................................... 137
Sizing a Solar Space Heating System ............................................ 143
Sizing Components ........................................................ ............ . 150
Sizing Expansion Tanks ............. .. .... ..................... ............... ........ 156
Sizing Air Heating Systems ....... .. ... .. ........................................... 157
Chapter 8: System Installation ...................................... ..... .. ... .. ... .. ... .. ....... 159
Installing Solar Water Heating Systems .......... .. ... .... ....... .. ... .. ....... 159
Handling Solar Collectors ........................................................... 161
Mounting Solar Collectors ........ .. .... ..... ..... ..... ..... .. ... .. ... .. ... .. ....... 165
Contents I VII
Mounting the Heat Exchanger ...... .......... ......................... ..... ...... 181
Plumbing the System ........................................................ .......... 184
Testing the System ...................................................................... 192
Installing Solar Pool Heating Systems ........... .. .. .... .. .. ........ .. ......... 193
Installing Radiant Floor Tubing ...................... .. .. ........................ 194
Chapter 9: System Operation and Maintenance ......................................... 203
Charging a Pressurized System .................................................... 203
Charging a High-Mass System ..................................................... 209
Finishing Up .............................................................................. .209
Controls and Power Sources ........................................................ 210
Maintenance .............................................................................. .218
Appendix A: Wire Sizing Chart .................................................................... .225
Appendix B: Metric Conversions ................................................................... 227
Appendix C: Temperature and Resistance Conversion Chart ............ .. ......... 229
for 10K Thermistors
Glossary ........................................... ............................................. ........... 231
Index ........................... ...... .................................................................. 235
About the Authors .............. .... ... .... .. ... .. ........................................................... 245
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