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WATER HEATERS

AGE of WATER HEATERS
AIRBOUND HEAT SYSTEM REPAIRS
ALTERNATIVE HOT WATER SOURCES
  Electric Shower Heaters
  High Efficiency Water Heaters
  Indirect-fired Water Heaters
  Instantaneous Water Heaters
  Multiple water heaters in parallel
  Multiple water heaters in series
  Range Boiler Water Heaters
  Side Arm Coil Water Heaters
  Solar Water Heaters
  Tankless Coil for Hot Water
  Tankless Water Heaters
ANODES & DIP TUBES on WATER HEATERS
ANTI SCALD VALVES
APPLIANCE EFFICIENCY RATINGS
AQUASTAT CONTROL Functions

BACKDRAFTING HEATING EQUIPMENT
BACKFLOW PREVENTERS
BACKUP HEAT for HEAT PUMPS
BLEVE EXPLOSIONS
BOILERS, HEATING

CARBON MONOXIDE - CO
CHECK VALVES
CHEMICAL CONTAMINANTS in WATER
CHIMNEY INSPECTION DIAGNOSIS REPAIR
CLOGGED SUPPLY PIPING
CROSS CONNECTIONS, PLUMBING

DEBRIS in WATER SUPPLY, Water Heater
DRAIN a WATER HEATER TANK

ELECTRIC WATER HEATERS

ENERGY SAVINGS in buildings

FLOODED HEATING EQUIPMENT REPAIR
FLOODED WATER HEATER REPAIR
FREEZE-PROOF A BUILDING
FROST HEAVES, FOUNDATION, SLAB

GALVANIC SCALE & METAL CORROSION
GAS BURNER Flame & Noise Defects

GAS FIRED WATER HEATERS

GAS PIPING, VALVES, CONTROLS

HEAT TAPES, Heat, Insulation prevent Freeze-Up
HEATING COST FUEL & BTU Cost Table
HEATING COST SAVINGS METHODS
HEATING SYSTEMS

HOT WATER SUPPLY
HOT WATER IMPROVEMENTS
HOT WATER DELIVERY SPEED UP
HOT WATER PRESSURE EXPANSION RATE
HOT WATER PRESSURE LOSS

HOT WATER QUANTITY IMPROVEMENT

HYDROGEN SULFIDE GAS

INDIRECT FIRED WATER HEATERS

MANUALS & PARTS GUIDES - HVAC
MIXING / ANTI-SCALD VALVES

NO HEAT - NO HOT WATER: HEATER DIAGNOSIS

NOISE / SOUND DIAGNOSIS & CURE
NOISE CONTROL for HEATING SYSTEMS
NOISE, PLUMBING CHECKLIST
NOISES, WATER HEATER

ODORS & SMELLS DIAGNOSIS & CURE
ODORS GASES SMELLS, DIAGNOSIS & CURE
ODORS IN WATER

OIL FIRED WATER HEATERS

PIPING IN buildings, Clogs Leaks Types
PLASTIC HEATER VENT

RADIANT HEAT
RANGE BOILERS
RELIEF VALVES - TP Valves on Boilers
RELIEF VALVES - Water Heaters
RELIEF VALVES - Water Tanks

SAFETY, HEATING INSPECTION
SCALE REMOVAL, WATER HEATERS

SEWER GAS ODORS

SOLAR ENERGY SYSTEMS
SOLAR HOT WATER HEATERS
SOOT on OIL FIRED HEATING EQUIPMENT
SPILL SWITCHES - Flue Gas Detection

TANKLESS COILS
  AQUASTAT CONTROL Functions
  Clogged Pipes / Tankless Coil De-Scale
  MIXING / ANTI-SCALD VALVES
  Tankless Coil Conversions
  Tankless Coil Leaks
  Tankless Coil Hot Water Increase

TANKLESS WATER HEATERS
  Electric Shower Heaters
  Guide to Tankless Water Heaters
  Operation & Characteristics
  Problems & Defects
  Hot Water Delivery Speedup
  Installation Requirements & Costs
  Should I Convert to a Tankless Heater?
  Calculate Water Heater Requirements
  Capacities of Tankless Water Heaters
  Life Expectancy & Applications

Temperature Pressure Relief Valves - Water Heaters
THERMOSTATS, HEATING / COOLING
THERMOSTATS, WATER HEATER
  AQUASTAT CONTROL Functions
  Electric Water Heater Thermostats
TIMERS for ELECTRIC WATER HEATERS

VALVES, PLUMBING

WATER CONTAMINANT LEVELS
WATER HAMMER NOISE DIAGNOSE & CURE

WATER HEATERS
WATER HEATER ALTERNATIVES
WATER HEATER ANODES, DIP TUBES
WATER HEATER AIR INLET
WATER HEATER DEBRIS FLUSH
WATER HEATER DRAIN PROCEDURE
WATER HEATER FLUSH PROCEDURE

WATER HEATER NOISES

WATER HEATER PROPERTIES

WATER HEATER SCALE - De-Liming Procedure
WATER HEATER SCALE PREVENTION
WATER HEATER SAFETY
WATER HEATERS for HOME HEATING USE?

WATER ODORS, CAUSE CURE

WATER PIPES, Clogs Leaks Types

WATER PRESSURE & FLOW MEASUREMENT
WATER PRESSURE GAUGE ACCURACY
WATER PRESSURE LOSS DIAGNOSIS & REPAIR
WATER PRESSURE REDUCER / REGULATOR
WATER PRESSURE REPAIR GUIDE - WELLS

WATER PUMPS, TANKS, TESTS, WELLS, REPAIRS

WATER PUMPS & WELLS
WATER PURIFIERS

WATER QUALITY TESTS, CONTAMINANTS, TREATMENT
WATER QUANTITY IMPROVEMENT

WATER SOFTENERS & CONDITIONERS

WINTERIZE A BUILDING

More Information

Tankless water heater (C) Carson DunlopOwner's Guide Converting to a Tankless Water Heater

Demand Water Heaters, Point of Use (POU) water heaters, Instantaneous Water Heaters
InspectAPedia®  -     

  • An owner's guide to tankless water heaters - hot water on demand
  • Tankless water heaters = demand water heaters = instantaneous water heaters
  • Detailed explanation of how tankless hot water heaters work, what they cost, what are their operating characteristics, pro's and con's.
  • Questions & answers about benefits of installing instant or demand or point of use water heaters
InspectAPedia offers impartial, unbiased advice without conflicts of interest. We will block advertisements which we discover or readers inform us are associated with bad business practices, false-advertising, or junk science. Our contact info is at InspectAPedia.com/Contact.htm.

This article explains the conversion from conventional hot water heaters to use of tankless water heaters, also called instant water heaters or "on demand" water heaters.

Readers should also see ALTERNATIVE HOT WATER SOURCES to distinguish among these types of hot water producing systems.

The original text of this article was provided courtesy of Carson Dunlop - that text has been edited and may not entirely reflect CD's views. Page top sketch of a point of use tankless water heater courtesy of Carson Dunlop. Our OPINION is that readers looking for plenty of hot water heated efficiently should also consider the heater we describe at Indirect-fired Water Heaters.

© Copyright 2010 InspectAPedia.com and Carson Dunlop Associates, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use page top links to major topics or use links at the left of each page to navigate within topics and documents at this website. Green links show where you are in a document series or at this website.

Should I Convert my Hot Water Supply to a Tankless Water Heater?

OPINION:

Most of us are familiar with the traditional-style water heater - that big thirty- to sixty-gallon tank taking up space in the basement near the furnace or boiler. These water heaters have served us well with few improvements for decades, but a different breed of water heater has been in use for many decades in Europe and Latin America, and has seen less widespread but growing popularity in the U.S. - the tankless water heater.

The energy-conscious world in which we live has turned its attention to the water heaters of old and has identified two potential areas of improvement. The first is that traditional water heaters are not very efficient at converting the energy in fossil fuels into hot water. Over the last twenty years, furnace and boiler technology has improved the efficiency of home heating, but water heaters have not kept pace, even though the same technology can be applied.

The second possible improvement that can be made to water heaters has to do with the storage of hot water. Traditional water heaters use fuel to heat water inside the tank. If the water is not used, it cools to the point that it must be heated up again.

The result is that we are constantly keeping a large volume of water at a high temperature, even if we are not planning on using any of it in the next little while. This means that while we are sleeping or at work, our water heaters are burning fuel or consuming electricity keeping a whole tank of water hot.

This is not a problem in the winter, when the heat loss from the water heater helps keep the building warm. It is a challenge in the summer, when the building is already warmer than we want. Tank-type water heaters can increase air conditioning costs.

As the name suggests, tankless water heaters have no tank, and therefore no storage capacity at all. When the faucets and fixtures in the home are sitting unused, the water heater is dormant. When somebody turns on a hot water faucet, the tankless heater swings into action.

These units use more powerful burners than conventional water heaters to heat relatively small amounts of water. The result is that the water is heated much more quickly than in an older system and this hot water can be immediately delivered to the fixtures.

A significant advantage of this system is that you can't empty all of the hot water out of the tank because there is no tank - just continuous hot water.

Also, since there is no tank, the water heater itself is much smaller. In most cases, these units are wall-mounted, so we not only do we have improved efficiency, reduced fuel costs, and unlimited hot water, but more free space in our basements!

While this all sounds good so far, there is a reason that everybody isn't switching over right away.

Conventional water heaters, due to their simplicity, are relatively inexpensive, while tankless water heaters are more expensive to purchase.

Their complexity also means that maintenance and repairs can be more expensive as well, and while tankless units have been in use around the world for many years, the rapidly evolving technology and our cold climate means that we don't have a great idea how long the typical life expectancy will be in North American homes.

Still, when it comes time to change your water heater, consider getting rid of that big tank and going tankless.

.

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Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

  Tankless Water Heaters
    Guide to Tankless Water Heaters
    Operation & Characteristics
    Problems & Defects
    Hot Water Delivery Speedup
    Installation Requirements & Costs
    Should I Convert to a Tankless Heater?
    Calculate Water Heater Requirements
    Capacities of Tankless Water Heaters
    Life Expectancy & Applications

  • Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. (416) 964-9415 1-800-268-7070 info@carsondunlop.com. Thanks to Alan Carson and Bob Dunlop, for permission to use illustrations from their publication, The Illustrated Home which illustrates construction details and building components. Carson Dunlop provides home inspection education including the ASHI-adopted Home Inspection Training Program (home study course), publications such as the Home Reference Book, report writing materials including the Horizon report writer, and home inspection services. Alan Carson is a past president of ASHI, the American Society of Home Inspectors.
  • Consumer Reports offers an article on the efficiency versus the economy of tankless water heaters - see http://www.consumerreports.org/cro/appliances/heating-cooling-and-air/water-heaters/tankless-water-heaters/overview/tankless-water-heaters-ov.htm
  • Bosch Tankless Water Heaters - http://www.boschhotwater.com/
  • Chromolite Tankless Water Heaters
  • Bradford White Everhot Tankless Water Heaters - Bradford White offers this step by step hot water retrofit installation file (large, slow PDF) - www.bradfordwhite.com
  • Eemax Tankless Water Heaters - http://www.eemaxinc.com/
  • Noritz Tankless Water Heaters - http://www.noritz.com/
  • Rheem Tankless Water Heaters - http://www.rheemtankless.com/content/
  • Rinnai Tankless Water Heaters - http://www.rinnai.us/tankless-water-heaters/
  • Stiebel Eltron Tankless Water Heaters - http://www.stiebel-eltron-usa.com/
  • Takagi USA Tankless Water Heaters - http://www.takagi.com/
  • Titan Tankless Water Heaters - http://www.titanheater.com/
  • U.S. Department of Energy on Tankless Water Heaters - http://apps1.eere.energy.gov/consumer/your_home/water_heating/index.cfm/mytopic=12820

Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair

  • Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.
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  • Plumbing Diagnosis & Repair: Water supply, drainage, septic systems, water testing, water contamination, defective plumbing materials & products.
  • Home Reference Book - Carson Dunlop The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 2010, $69.00 U.S., is available from Carson Dunlop. The Home Reference Book is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. InspectAPedia.com ® author/editor Daniel Friedman is a contributing author. Field inspection worksheets are included at the back of the volume.
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