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Mobile ViewWATER 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 PREVENTER VALVE, HEATING SYS BACKFLOW PREVENTER, HEATER WATER FEEDER BACKUP HEAT for HEAT PUMPS BLEVE EXPLOSIONS BOILERS, HEATING CARBON MONOXIDE - CO CHECK VALVES, WATER SUPPLY CHEMICAL CONTAMINANTS in WATER CHIMNEY INSPECTION DIAGNOSIS REPAIR CLOGGED DRAIN DIAGNOSIS & REPAIR CLOGGED SUPPLY PIPING CROSS CONNECTIONS, PLUMBING DEBRIS in WATER SUPPLY, Water Heater DRAIN a WATER HEATER TANK ELECTRIC WATER HEATERS Electric, Gas, Oil Water Heater Efficiency Electric Shower Heaters Electric Water Heater Checklist Electric Water Heater Controls List Electric Water Heater Element Replacement Electric Water Heater Element Tests Electric Water Heater High Temp Cutoff Test Electric Water Heater Repair Guide Electric Water Heater Reset Switch Electric Water Heater Thermostats Electric Water Heater No Hot Water Electric Water Heater Parts Identification Electric Water Heater Reset & Temp Set Hot Water Temperature & Pressure Valve Timers for Electric Water Heaters Water Heater Anode & Dip Tube Check 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 DRAFT HOODS - gas fired Gas BTUH & Cubic Feet Gas Conversion LP Natural Gas GAS PIPING, VALVES, CONTROLS SOOT on OIL FIRED HEATING EQUIPMENT SPILL SWITCHES - Flue Gas Detection 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 EFFICIENCY IMPROVEMENT HOT WATER PRESSURE EXPANSION RATE HOT WATER PRESSURE LOSS HOT WATER PROBLEM DIAGNOSIS HOT WATER QUANTITY IMPROVEMENT Alternative Hot Water Sources & Methods Anti-Scald Valves & Hot Water Quantity CLOGGED PIPING & Hot Water Flow Extra Tanks to Increase Hot Water Insulate Hot Water Piping Insulate Hot Water Tank? Larger Diameter Water Supply Piping Water pipe clog diagnosis Water pipe clog repair guide 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 NOISE, WATER HEATER 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 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 EFFICIENCY WATER HEATER FLUSH PROCEDURE WATER HEATER NOISES WATER HEATER PROBLEM DIAGNOSIS WATER HEATER PROPERTIES Electric, Gas, Oil Water Heater Efficiency Water Heater Life Expectancy Comparisons Water Heater Operating Cost Comparisons Water Heater Purchase & Maintenance Costs Water Heater Water Quantity Comparisons Water Heater Recovery Speed Comparisons Water Heater Safety Comparisons WATER HEATER EFFICIENCY 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 |
Hot water heater properties: this article describes how to compare the operating characteristics such as safety, capacity, life expectancy, and operating cost of alternative methods of providing domestic hot water for washing and bathing. InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers nor with topics or services discussed at this website.© Copyright 2012 InspectAPedia.com, 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. A Comparison of the Properties of Types of Hot Water HeatersThanks to Carson Dunlop, a Toronto Home Inspection Firm and Home Inspection Educator, for permission to use sketches shown in this article. This article on water heater characteristics describes and compares the following properties of different kinds of water heating systems and appliances:
Water Heater Life Expectancy Comparisons Ways to improve total hot water quantity, pressure, temperature and flow are discussed beginning at HOT WATER IMPROVEMENTS and continuing at HOT WATER QUANTITY IMPROVEMENT. The following articles discuss alternative ways to produce domestic hot water for washing and bathing.
The characteristics of various water heaters such as life expectancy, cost, safety, and capacity are discussed at WATER HEATER PROBLEM DIAGNOSIS A Comparison of the Relative Life Expectancy of Different Types of Water HeatersHere is a rough guess at the relative life expectancy of these types of water heaters, provided all other water heater life factors (discussed at AGE of WATER HEATERS) are the same (comments are invited Contact Us) - water heaters are listed in their order of typical life from shortest to longest:
Conditions Affecting Water Heater LifeKeep in mind that conditions besides the type of water heater can dominate its life expectancy. Some of these water heater life expectancy factors include:
For complete information about water heater life and things that affect how long a hot water heater will last, see our full article at AGE of WATER HEATERS. How to Evaluate the Present and Future Relative Operating Cost of Different Types of Water Heaters: definition of therms
What is the Definition of a Water Heater Therm?In the U.S. natural gas is sold to consumers sometimes measured in therms (th). Therms is also used in Energy Guide ratings useful for comparing alternative water heater operating costs. A therm is the amount of natural gas used to generate 100,000 BTUs of energy. A therm (th) is thus also a measure of heat content, or a measure of energy usage. Since this is a simple fixed number, it's easy to compare gas-fired water heater efficiencies. Example: If water heater A uses 1 therm to produce 100 gallons of hot water heated up from 40 degF to 120 degF, and water heater B uses 2 therms to produce the same 100 gallons of hot water heated up from 40 degF to 120 degF, then water heater A will cost half as much to operate as water heater B. In other words, the fewer therms/gallon or therms/estimated-annual-usage-in-gallons, the higher is the efficiency and lower the operating cost of a given water heater. Relative purchase and maintenance cost of water heatersIn order of cost from least-costly to most-costly to purchase and maintain we estimate this order of types of water heater:
Remember to Include Water Heating Method Conversion Costs When Changing Water HeatersHot Water Quantity: A Comparison of the Relative Total Hot Water Capacity of Different Types of Water HeatersAny water heating method that stores hot water in a tank will provide about the same total hot water capacity if the tank is the same size. This includes electric, gas, oil fired water heaters and side-arm coil water heaters or range boilers, all of which use a water storage tank. Instantaneous water heaters, also called tankless water heaters, can provide effectively endless hot water but usually in limited quantity to the one or two fixtures supplied by the heater. Tankless coils provide a more limited quantity of hot water, depending on the amount of heat stored in the heating boiler (a function of its size and materials of construction - steel has less heat storage than cast iron), the temperature of the incoming water, the use of mixing valves, and the flow rate through the coil. Most tankless coils are rated as capable of providing a specific temperature degree rise across the coil, from input to output, at a specified boiler temperature and at a specified water flow rate in gallons per minute (often 5 gpm). If the water flow rate is faster than specified the coil will not heat water to as high a temperature. Relative Hot Water Recovery Rate/Speed of Different Types of Water Heaters - What is the recovery rate of a water heater?
As we illustrate with Carson Dunlop's sketches shown here, in order of speed of re-heating or hot water recovery time, listing slowest-recovery time to fastest recovery time we'd list water heater types as follows:
Don't confuse water heater recovery rates (how fast we can heat water) with water heater operating costs, which we discuss at Water Heater Operating Cost Comparisons. Recovery rate is measured in gallons per hour or gph. Water heater operating costs are compared using a standard measure of energy cost in therms. A Comparison of the Relative Safety of Different Types of Water heatersSee our complete list of water heater safety features and devices found at WATER HEATER SAFETY.
Most critical in determining the safety of any water heater is that the heater is properly installed and includes the required safety controls such as those responsible for limiting temperature and pressure. Any water heater should include a temperature and pressure relief valve installed of the proper type and at the correct location. Gas-fired devices also should include flue-gas spillage detectors. Oil-fired devices should also include a fire-safety valve that shuts off fuel to the appliance in case of fire. We guess that proper installation, inspection, and maintenance make more difference in the safety of a water heater than the innate differences among heater types, fuels, etc. Some Hot water heater safety devices and featuresSee our complete list of water heater safety features and devices found at WATER HEATER SAFETY. Excerpts are below.
Questions & Answers regarding this articleQuestions & answers about the properties, costs, efficiencies, and performance of different types of residential hot water heating systems. Ask a Question or Search InspectAPediaHTML Comment Box is loading comments...
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