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AGE of WATER HEATERS
AIRBOUND HEAT SYSTEM REPAIR by WATER FEED VALVE
ALTERNATIVE HOT WATER SOURCES
ANODES & DIP TUBES on WATER HEATERS
ANTIFREEZE for BOILERS
ANTI SCALD VALVES
APPLIANCE DIAGNOSIS & REPAIR
APPLIANCE EFFICIENCY RATINGS
AQUASTAT CONTROL Functions
BACKDRAFTING HEATING EQUIPMENT
BACKFLOW PREVENTER, HEATER WATER FEEDER
CARBON MONOXIDE - CO
CHECK VALVES, WATER SUPPLY
CHEMICAL CONTAMINANTS in WATER
CHIMNEY INSPECTION DIAGNOSIS REPAIR
CLOGGED SUPPLY PIPING
DEBRIS in WATER SUPPLY, Water Heater
DRAIN a WATER HEATER TANK
ELECTRIC WATER HEATERS
FLOODED HEATING EQUIPMENT REPAIR
FLOODED WATER HEATER REPAIR
GALVANIC SCALE & METAL CORROSION
GAS BURNER Flame & Noise Defects
GAS FIRED WATER HEATERS
GAS PIPING, VALVES, CONTROLS
HOT WATER SUPPLY
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
PIPING IN buildings, Clogs Leaks Types
PLASTIC Plexvent / Ultravent RECALL
PLUMBING FIXTURES, KITCHEN, BATH
RELIEF VALVE LEAKS
RELIEF VALVES - Water Heaters
SCALE REMOVAL, WATER HEATERS
SEWER GAS ODORS
SOLAR HOT WATER HEATERS
SOOT on OIL FIRED HEATING EQUIPMENT
SPILL SWITCHES - Flue Gas Detection
TANKLESS WATER HEATERS
Temperature Pressure Relief Valves - Water Heaters
THERMOSTATS, WATER HEATER
TIMERS for ELECTRIC WATER HEATERS
WATER CONSERVATION MEASURES
WATER CONTAMINANT LEVELS
WATER HAMMER NOISE DIAGNOSE & CURE
WATER ODORS, CAUSE CURE
WATER PIPES, Clogs Leaks Types
WATER PRESSURE & FLOW MEASUREMENT
WATER PRESSURE LOSS DIAGNOSIS & REPAIR
WATER QUANTITY IMPROVEMENT
WATER SOFTENERS & CONDITIONERS
WINTERIZE A BUILDING
Electric water heater repairs: here we explain how to install, troubleshoot, & repair electric water heaters. We describe the types of water heaters, the parts that make up an electric water heater, and here we provider a checklist for inspecting or troubleshooting electric water heaters. This article also provides links to detailed water heater diagnosis and repair articles found free at this website.
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This series of articles describes how to inspect, operate, diagnose, and repair electric hot water heaters. The articles at this website will answer most questions about electrical water heaters as well as many other building plumbing system inspection or defect topics. This page contains links to in-depth articles on inspecting, testing, and repairing problems residential hot water heaters of all types, including their parts, controls, and alternative sources for hot water as well as tips for improving hot water temperature, hot water pressure, and hot water quantity. Reproduction of this web page electronically at other websites is prohibited.
The sketch at left shows the basic components of an electric water heater and is provided courtesy of Carson Dunlop Associates. It's easy to identify an electric water heater:
But watch out: sometimes an electric water heater is installed as an additional or backup hot water source, so you'll also want to see if you have other hot water heating equipment installed, such as a Tankless Coil for Hot Water.
Water heater anode inspection and repair - see ANODES & DIP TUBES on WATER HEATERS
Drains: Water heater drain valve leaks: Check for leaks at the water heater drain valve. Most water heater manufacturers recommend that their water tank be drained periodically.
This process will help remove sludge and debris or mineral deposits that may have accumulated at the bottom of the water heater tank.
Removing this debris can extend the life of the hot water tank, especially where electric and gas fired water heaters are involved. But since few people remember to open and drain the tank it may be that the drain valve does not open easily, or worse, it won't close. For details also see How to Drain a Hot Water Heater Tank
Heating Elements: how to test and repair a bad electric water heater heating element see Electric Water Heater Element Tests to determine if your water heater has a bad element, and if so, see Electric Water Heater Element Replacement
Insulation: Water heater insulation: look for insulation that has been improperly added to the water tank - it may be unsafe. See Insulate Hot Water Tank?
Leaks: Water heater leaks: Look for evidence of leaks in the hot water tank, or mechanical damage, or improper installation. For example most water heaters are intended to be installed in a vertical position. Installing a hot water tank horizontally or in a hole in a crawl space is likely to cause early failure of the heater, violate the manufacturer's guidelines, and may be dangerous. In our photo at above left an oil-fired water heater and an indirect-fired water heater are installed in tandem. That puddle on the floor needs investigation.
Mobile Homes: Water heater in mobile home: common defects - see MOBILE HOME WATER HEATER DEFECTS
Noises: Water heater clanking noises: check the electric hot water tank for lime, mineral, or silt deposits and build-up on the tank bottom and on the heating electrodes. Water heater hissing noises: on an electric water heater a hissing sound may be noticed when the heater is operating. This sound may be due to mineral scale or lime build-up on the heating electrodes. Remove, inspect, and clean the electrodes when this sound is observed. See WATER HEATER NOISES for details.
Water heater odor sources, causes, diagnosis, cure:
Odors or smells from or near the water heater, including sulphur or rotten egg odors (possibly dangerous), particularly if the heater has been left shut off and out of use for two weeks or more. Details are at HYDROGEN SULFIDE GAS.
Smells: Odors in hot water, particularly a sulphur smell may be due to a bacterial contamination in the hot water tank or due to a failing hot water heating tank sacrificial anode. See ANODES & DIP TUBES on WATER HEATERS. Also see ODORS IN WATER.
Also CHINESE DRYWALL HAZARDS discusses Chinese drywall odors, sulphur smells, and corrosive outgassing hazards in buildings. Major costs to remove this product, repair or replace electrical wiring, plumbing, and HVAC components may be involved, and there may be immediate safety hazards due to damaged smoke detectors or carbon monoxide detectors in buildings where Chinese drywall outgassing has caused damage.
Pipes & Valves: Water heater piping & valves: check the piping and control valves connected to the water heater for leaks, support, and for proper location of shutoff valves. An improperly installed shutoff valve on a water heater can be very dangerous, risking an explosion. Usually the "hot water tank shutoff valve" is installed only on the cold water pipe coming into the water tank. There should be no shutoff valve installed on the hot water line leaving the water tank.
Relief Valve: Water heater temperature/pressure relief valve: Check the pressure and temperature relief valve on your water heater: look for evidence of corrosion, leaks, improper installation, etc. If the water heater relief valve is dripping or leaking, check for
A missing, modified, blocked, or leaky pressure relief valve is extremely dangerous and can lead to a catastrophic BLEVE boiling liquid vapor explosion that can cause severe damage or even fatalities at a building. For details about water heater relief valves, please see Testing the Water Heater Temperature Pressure Relief Valve, and also see RELIEF VALVES - TP VALVES for heating equipment in general
Scale: Water heater scale, clanking noises, or reduced hot water quantity or temperature: see WATER HEATER NOISES for details about removing scale from a water heater. Water heater scale forming on electric water heater elements can cause water heater element failure, water heater noises, or reduced water heater output.
Temperature: Water heater temperature settings: Check the settings of the water heater temperature:
See Temperature of Hot Water is Too Low. On an electric water heater, temperature settings are usually made on a control hidden behind the upper and/or lower removable access panel covers that give access to the upper and lower heating element.
On a single element electric water heater, if the heating element has burned out there will be no hot water at all. On a dual heating element electric water heater, too little quantity of hot water can be traced to a burned-out lower element, while plenty of "hot" water that is never very hot can be traced to a burned-out upper water heater element. See Electric Water Heater Element Tests.
If the water heater is too hot there is a risk of scalding burns - check the electric water heater thermostat settings and also see ANTI SCALD VALVES.
Green link shows where you are in this article series.
Frequently Asked Questions (FAQs)
Question: how to find the source of a leak in a water heater
i have a reddring 210 water heater since 2001. the engineer could not locate the leak, which seems coming out from the base. he recommended a new one. any suggestion please. - Michael 8/20/11
Michael, if your water heater is leaking from the tank itself and not just at a fitting such as at threaded fittings for a relief valve or control, then indeed it needs to be replaced.
Question: water heater relief valve leaks after the heater has been busy
no matter what tenp i set the thermostat at the trv lets out a about a 1/2 a cup of water after a hard use - Steve 7/30/12
Steve, there are several conditions that can cause spillage from the temp/press relief valve on a water heater, including overheating, overpressure, water hammer, and leaks or defects in the valve itself.
Don't hesitate to ask if questions remain after reading that pair of articles.
Question: how to diagnose bad odors seem to be coming from our water heater
Since mid - december we have experienced a bad chemical odor in our garage where the electric hot water heater is, we've cleaned out the garage but the smell came back as soon as someone used something with hot water, what should we do? - Jackie 1/31/2013
Jackie, in the article above we list several odor problems that are traced to water heaters, from which I excerpt the two most common problem sources: bacterial contamination in the water heater or a bad sacrificial anode. You could also ahve sulphur in your building water supply but I figure you'd notice that first in the cold water.
Smells: Odors in hot water, particularly a sulphur smell may be due to a bacterial contamination in the hot water tank or due to a failing hot water heating tank sacrificial anode.
Odors or smells from or near the water heater ...sulphur or rotten egg odors..., particularly if the heater has been left shut off and out of use... are explained at HYDROGEN SULFIDE GAS.
Question: should I have 240v at both water heater elements at the same time?
(Jan 13, 2012) jeff warren said: should i have 240v at both water heater elements at the same time?
Reply: No not necessarily.
Jeff, not all electric water heater hookups are the same; there are 120V models, 240V models, one element and dual element, and variations on whether both elements heat at the same time or not.
In addition even some 240V electric water heaters stage the control of heating elements, turning on only one element depending on the temperatures and demand.
You'll want to get a copy of the wiring diagram for your particular water heater model. If you are having trouble finding those instructions let me know and I'll help dig them up. For some typical wiring examples, American Water Heater Co. has lots of water heater wiring diagrams online for their models as well.
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