Ran out of warm water? You can easily patch (and substitute if necessary) the controls and heating elements of most commonplace residential 120, 208 and 240 volt electric water heaters with traditional queue voltage controls; no the microprocessor types that are starting ought appearance at stores. Further, it does no debate gas or propane fuel types nor plumbing related issues. This is a detailed, comprehensive prose with additional assist above the discussion page.
1. Repairing a Heater
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1) check electric panel ought exist definite that circuit breaker is at the "On" post (not at tripped or off) or fuses (if used) are installed securely and no "blown". Reset circuit breaker ought "On" or substitute any blown fuse(s) and wait 30 - 60 minutes although the water ought warm. if water has remained cool, bear troubleshooting steps below.
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2) finish off the power. Most water heaters are supplied by voltages that can meditate shock, burns and flat death ought an energized conductor grow at encounter with the body. finish off energy at the electric panel by removing fuses or by moving the dispose of of a switch or circuit breaker dedicated ought the water heater ought the Off position. Completely shift and "pocket" the fuses or otherwise earn or lock the panel and put a note above the cover ought alert everyone that profession is being performed above the water heater circuit. This will block the accidental energizing of the circuit while you are working above it.

3)
Remove the upper (and if provided lower) access panel(s). The metal covers are frequently held at put with screws. shift the screws and maintain although reinstallation while done. employ a voltmeter or experiment gaze ought check between wiring terminals and the grounded metal instance of the tank ought exist definite that the energy is off. if energy is cabin on, conduct no impress at until you locate the dissolve or circuit breaker supplying power. Lock off or earn the circuit breaker or shift fuses ought block someone from turning the circuit above while you are working above the water heater.

4)
Clear away any insulation blocking access or progposal of the controls (thermostat and high-temperature switch) and heating element. Once the thermal insulation has been removed, elastic impact protectors are visible. Carefully fold any wires away from the protective cover. arise the tab at the peak away from the clip and shift ought access terminals.
- View with elastic impact protector removed:

5) appearance although obvious signs of damage. Water heaters can leak although a arise of a failing tank - besides either because of poorly fitted or soldered chilly water furnish pipe / warm water output pipe or a bad seal between tank opening and heating element. if allowed ought bear ought leak, it will meditate internal ruin ought the controls ought water enter them.
- Rust coats wires and controls - both outer and inside
- Rust is conductive - flat while above the rope insulation. This can direct ought potentially fatal shocks, heating and melting insulation and flat burns. Sooty, dark carbon deposits above surfaces imply a short circuit. Chances are there is an exposed copper wire that can exist difficult ought yell on because of the carbon deposits that resulted from the short circuit.
- Wires can consume been damaged and now tolerate with a reduced circumference that is needed ought safely cost the heating component electric load. This point of ruin either becomes a source of heat. It is too important ought patch or substitute sum parts that consume visible forms of water and short circuit damage. This includes wires, rope insulation, jumpers and the controls themselves. although mentioned above, rust is a conductor and provides unintended and unexpected paths although electricity. These unintended paths can exist dangerous and invent troubleshooting too difficult ought perform.
- Here, the yellow rope between the fundamental and component appears ought consume shorted ought the tank (or other metal) leaving a sooty dark deposit above the rope and above. note the lower left station of the thermostat. Excessive fever has caused the elastic almost the station ought vacation ought melt.

6) Locate the parts below:
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High Temperature frontier Switch: Has a reset button There will exist (4) station screws / wires connected ought it. Usually, the peak two terminals consume wires that impress at up ought the sphere wiring compartment that cost the energy ought the console of the water heater's controls and heating elements. The "upper controls" include of the High-Temperature frontier Switch and Upper Thermostat. The "lower controls" refers ought the Lower Thermostat (there is no High-Temperature frontier Switch although the lower part of most electric water heaters). Three of the four terminals are numbered and visible at the film (#1, #3, & #4; the #2 station is no identified although it is connected direct ought the thermostat below via factory installed jumper).
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Thermostat: Has a graduated, adjustable dial. The dial can imply letters "A" "B" "C" etc., "warm, warm and hotter" or although at the instance of the one pictured, the genuine temperature at degrees. The thermostat is located fair below the high Temp frontier Switch.
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Heating Element: Has two terminals with a rope connected ought each. One of these wires is frequently connected ought the thermostat associated it (in these photos the thermostat is direct at it). It is frequently located below the controls and supports the controls with a clip of some classification (in this photo, it has two terminals and a gray metal clip attached ought uphold the controls above).
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7) experiment ought assure energy is off. put the meter although AC Volts and insert the dark probe into the dark or commonplace jack, and the red probe into the red or Volts jack.

8)
Measure Voltage. put the AC voltage mount ought the highest available. affect the probes ought the peak terminals of the high temperature frontier switch although shown at the image ought the right. if desired, the mount can exist lowered ought any desired - provided the mount is greater than the voltage displayed at the highest range. if unable ought prove energy off, double check circuit panel. conduct no impress at unless energy is proved off; otherwise ruin ought meter is apt and impact or burns is possible at the steps that follow.
- In the provided picture, the meter indicates 0.078 volts present. This is less than 1/10 of a volt, and is considered "off".
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9) put the multimeter ought Ohms or Resistance. look the meter indication. if an analog type, the needle or pointer will exist resting at at the higher resistance values (left-most position) this is an "open circuit" indication. if digital meter is used, it can description "OL" or "1" ("1" without trailing or chief zeros). This OL or 1 symptom represents a impose greater than the meter is capable of displaying (similar ought the manner a calculator does) although "overload" or "infinity". Infinity at high resistance mount is either called an "open circuit" or "Open Loop" (OL). accept note of this vacant circuit symptom although this meter (when at a voltage or tendency mount is selected and the meter displays OL or 1, the measurement ought exist taken again backward adjusting the mount upward). if you are unsure what your meter ought scan at an "OL situation", fair desert the terminals unconnected ought anything and no touching each other and switch the meter on, it ought then imply the resistance of the stand between the terminals which ought exist infinity at conventional conditions.
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10) shift one rope from the heating element, it does no affair which.
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11) mingle the dark experiment direct ought the jack marked "Common".
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12) mingle the red experiment direct ought the jack marked "Ohms" or "Resistance" if there are multiple jacks from which ought choose.
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13) put the mount (if provided) ought R x 1. if the meter being used does no furnish although mount selection, it is apt an "autoranging" type. This simply manner that the meter will automatically wear the mount up or down although needed without any intervention by the user. This quality is distant more commonplace above digital meters than analog types. Most analog meters that conduct no furnish manual mount preference apt uphold unique a unique range. These meters are much more right indicating represent values (such although 0 over 500k or 1M ohms) than higher values (such although those at 1M), besides will profession vigorous although this procedure. wage finish attention ought the description of an auto-ranging digital meter while reading - there is a enormous difference between 20, 20K and 20M ohms. A "K" indicates thousands, and an "M" indicates millions. The examples at used to correctly exist scan although 20 ohms, 20,000 ohms (20K ohms or 20 kilo ohms) and 20,000,000 ohms (20 meg ohms or 20 million ohms). each is 1000 mature larger than the previous.

14)
Press the metal tips of the experiment probes together. The analog meter pointer ought impress ought lowest values of the resistance scale (or fully ought the right). The digital meter ought imply 0 or a "very low" impose approaching zero. Locate the "Zero Adjust" knob and grow consequently that the the meter indicates "0" (or although finish ought "0" although possible). Most digital meters conduct no consume this Zero wear feature. Once "zeroed", this needle post above the dial is the "short circuit" or "zero ohms" symptom although this mount of this meter. The meter
must exist zeroed if the resistance mount is changed.
Measured resistance values will exist inaccurate if unable ought properly zero the meter.
- In the instance picture, the meter indicates 0.2 ohms resistance - or zero. The meter can no description a impose lower than this value, because there is no zero wear quality it is considered 0.
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15) substitute batteries if needed. if unable ought earn a zero ohm symptom above an analog meter, this can intend the batteries are feeble and ought exist replaced. Retry the zeroing step at again with fresh batteries. Digital meters frequently graphically description the battery's even of eliminate or simply an symptom ought substitute the battery. check the meter manual although assist determining the battery condemn state.

16)
Press the probe tips against the terminals of the heating component (one probe ought each screw). scan the meter display. appearance although a mount multiplier (a "K" or "M" at the display) ought exist definite the impose displayed is indeed ohms, no kilo ohms (K) or meg ohms (M).
- In the provided picture, the meter indicates 12.5 ohms resistance, and because is within acceptable limits of the calculated 12.2 ohms value, it is considered "good".

17)
Be aware that a "good" heating component will scan a too represent impose (between 10 and 20 ohms depending above wattage of the component and perhaps scan although 0 ohms depending above your meter). ought determine the resistance impose although a good element, employ this online calculator. furnish the voltage (likely 240)and wattage (likely at the mount of 1000 ought 5000) ratings from the nameplate and click above the "calculate button".
- The film displays the "nameplate" news of the water heater. Two various wattage ratings are provided (4500 / 4500 and 3500 / 3500). The "4500 / 4500" rating is the wattage rating although the upper and and lower component respectively, while connected ought a 240 volt supply. Alternatively, the "3500 / 3500" rating is the wattage of the upper and lower component respectively, while connected ought a 208 volt supply. Most residential applications are 240 volts, besides 208 volt and 120 volt types are either found.
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18) check although a grounded element. Prepare the meter by locality the meter ought highest resistance scale.
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19) involve the probes at the purpose of the experiment leads together. The analog meter pointer ought impress fully ought the lowest values of the resistance scale (to the right). The digital meter ought imply a "low" impose too finish ought zero. Locate the "Zero Adjust" knob and grow consequently that the the meter indicates "0" (or although finish ought "0" although possible). The digital meter can no consume this Zero wear feature. note that this post is the "short circuit" or "zero ohms" symptom although this especial resistance mount of this meter. frequently "zero" the meter while changing resistance ranges.

20)
Press the red probe against either station screw of the heating element. journal the dark probe firmly against the metal tank or the heating component mounting nuts or screws (not the other station screw). Scrape the metal ought assure a good contact. The meter ought description the "infinity" symptom although described at at the meter setup. if the meter displays a impose other than a too high impose (millions of ohms), preferably infinity, the component ought exist replaced, described later.
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21) Reconnect the rope that was removed from the heating component ought conduct the resistance check at the preceding steps.

22) 'Repeat the steps needed ought earn access ought the lower thermostat and heating element.
- Lower access panels removed, exposing the elastic impact protector:
- #* shift protector although done although upper access point at ought disclose the terminals. note that there is no reset button (high limit) above the comparable the top:
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23) put the bottom thermostat ought minimum.
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24) put the peak thermostat ought maximum.
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25) The steps below presume that there is warm water at the tank. if the tank is chilly or too hot, it can exist difficult ought earn the expected changes while dialing at various temperatures above the thermostat.
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26) restore energy ought water heater. The console of the steps consume energy above although continued testing. employ extreme caution although the danger of impact injury is greatly increased if no fully paying attention. Ensure sum wires are reconnected ought respective terminals and there are no "accidental conductors" anywhere that could meditate a impact or short circuit.
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27) shift red experiment direct from the "Ohms" or "Resistance" jack of the meter and insert into "Volt" jack.
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28) put the mount of the meter ought the lowest Voltage impose that is greater than 240 Volts "AC" or "VAC". although mentioned earlier, commonplace voltages although residential (and mobile family / RV) classification water heaters are: 120, 208 & 240, with the most commonplace being the 240 volt variety. while steps below debate measuring "line voltage", representative the voltage although your especial water heater instead.

29)
Check the peak heating element's terminals although presence of queue voltage by touching a probe gift ought each terminal, although done at the resistance experiment earlier. queue voltage is apt 120, 208 or 240 at the U.S.
- The queue voltage at the system below experiment is 208 volts. because 203 is within a few percent of 208, this instance indicates entire energy available ought the component and if it passed the resistance or ohms experiment at - is heating the water at the tank.
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30) if there is no power, attempt ought reset the high temperature switch. It is a button either red or black, located direct at the thermostat. It most apt has "RESET" printed above it. With a screwdriver or pencil, GENTLY besides firmly journal in. if it is tripped, a mechanical "click" ought exist felt or heard. A tripped high temp switch is indicative of a thermostat that will no open. More above this, later.
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31) backward attempting reset, check the heating component although energy again.
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32) if cabin no energy present, experiment the peak left and accurate terminals of the high temp switch although queue voltage with the probe tips.
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33) if no power, bother is an vacant circuit. check the heater's "field wiring compartment" (usually located above the peak of the heater), over the length of the Cable that feeds the heater, and eventually inner the electric panel. Remember, unless energy is shut off at panel, this circuit is live at some point between the dissolve or circuit breaker and the water heater. Tighten any and sum wirenuts and connections at the wiring compartment and inner any junction boxes between here and sum the manner help ought the terminals of the circuit breaker or fuses at the electric panel. substitute vacant fuses or reset any tripped circuit breaker if off. check although energy at dissolve or circuit breaker. A circuit breaker that soon trips backward resetting indicates a short circuit or less likely, defective circuit breaker.
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34) Once energy is restored ought peak terminals of high temp switch, experiment although queue voltage at the peak heating element. scan the console of this step slowly and carefully (and frequently if needed) until it makes sensation although it is the "why and how" the thermostats profession together. The key is ought know how the two thermostats interact and responsibility differently. The peak thermostat has 2 positions - it can switch voltage ought "one post or the other": (position 1) ought the peak component or (position 2) ought the lower thermostat. The lower thermostat either has 2 positions besides it is "on and off", nobody or the other comparable the peak thermostat: (position 1) ought the lower component or (position 2) block voltage from reaching the lower component or anywhere else although that matter. In bid although the peak component ought consume voltage and fever the water, the temperature of the water at the peak of the tank have ought exist lower than the temperature locality of the peak thermostat. Once the water at the peak isolate of the tank has reached the temperature impose determined by the peak thermostat setting, the peak thermostat (is considered "satisfied") switches energy from the peak component ought the lower thermostat. if the temperature of the water at the bottom isolate of the tank is higher than the lower thermostat's setting, the lower thermostat rest "off" and voltage is prevented from reaching the lower heating element. if however, the temperature of the water at the bottom isolate of the tank is lower than the locality of the lower thermostat, the lower thermostat switches "on" and sends voltage ought the lower heating component (a thermostat that has switched energy ought a heating component or cooling compressor is said ought exist "calling") and heats the water. The voltage will remain above the lower component until either (a) the bottom thermostat is satisfied or (b), the peak thermostat detects that the temperature of the water at the peak of the tank has fallen below the temperature locality of the peak thermostat. while this occurs, the peak thermostat switches the energy from the lower thermostat help ought the peak heating element. This deed continues until the water at both halves of the tank is match ought the settings of their respective thermostats. locality the peak thermostat higher will no meditate the peak component ought grow above if the water temperature at the peak of the tank is already higher than the highest locality of the thermostat. if this conditions exists, no click will exist detected while turning the temperature locality up and down. It will exist indispensable ought lower the temperature of the water at the tank. The easiest and quickest manner ought conduct this is ought rent warm water out of the tank by simply opening a warm water faucet. chilly water will enter the bottom of the tank and mingle with the existing warm water at the tank, lowering the overall temperature.
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35) if queue voltage no build at the component and the peak tank is cool, substitute peak controls.
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36) put peak thermostat ought minimum.
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37) put lower thermostat ought maximum.
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38) check bottom heating component although presence of queue voltage.
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39) if no energy present, determine which rope is connects a heating component station screw ought the bottom thermostat station screw. These will exist the commonplace screw terminals. The other screw above the thermostat and heating component will exist the energy screw terminals. affect red probe ought the energy screw station of heating component and dark probe ought the energy screw station of thermostat. wish queue voltage.
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40) if queue voltage no found, substitute upper controls.
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41) if queue voltage found, check although queue voltage at heating component station screws by touching each probe ought the station screws.
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42) if queue voltage no build and the tank is cool, substitute lower thermostat.
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43) if queue voltage is found, wait although water ought fever or conduct the Ohms (or Resistance) checks above the elements once more with the energy off. if queue voltage is gift above a heating element, it have ought fever the water unless the component has failed.
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44) reply sum thermostats ought an match impose of your choosing, besides indeed ought no exist put higher than 140 degrees because of the danger of scalding. while water boils at 212 degrees, a water temperature of unique 150 degrees takes fair two seconds ought meditate a burn. while the water is 120 degrees, fair 30 degrees cooler; it takes 10 minutes. The leather of children and infants is more sensitive than that of an adult, and will burn more easily. owing ought this, selecting a temperature closer ought 120 degrees can exist a better choice. Lower temperature settings translate ought reduced energy costs, too.
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45) substitute insulation and access covers.
2. Replacing Elements
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1) assure energy ought water heater is off at the fuse, circuit breaker or "service switch".
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2) The heating elements protrude into the tank and are immersed direct at the water of the tank. although this reason, the water even at the tank have ought exist lowered ought a point below the even of the component ought exist removed (otherwise water will leak out although the component is removed). if removing the lower component or unsure how much ought drain, emptying the tank's sum contents will block unexpected spilling of water.
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3) ought quickly drain and fill the water heater, finish off the chilly water furnish ought the heater. vacant the nearest warm water faucet ought console vacuum stress and rent stand into the tank although it drains. mingle a garden hose ought the drain valve at bottom of the tank and extend the hose ought a floor drain or some other point that is lower than the drain valve as the tank will unique drain down ought the highest point of the hose. vacant drain valve at the bottom of the water heater and drain the tank.
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4) finish the tank's drain valve while the tank is empty (or emptied ought the point you desire).
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5) Disconnect wires from the terminals of the heating elements.
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6) The heating elements are secured by one of few methods. The first manner is by bolts that are installed over holes at a flange almost the element. Simply employ a socket and ratchet or other vigorous wrench ought shift the 4 bolts and shift the element. The second manner is by a threaded part of the component body that is build below a hex shaped flange of the element. Usually, a 1-1/2" socket will wear perfectly. if a socket of that size is no available, employ of a water heater component wrench, channel-lock mode pliers or adjustable wrench will earn the profession done quickly. crook the component counter-clockwise until it is loosened enough ought revolve out completely by hand.
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7) sweep the tank surface almost the opening although the element. It is important that sum gasket material, filings, rust etc., exist completely removed ought expose although flat a surface although possible. A rope brush and / or sandpaper rubbed at the opening ought invent simple profession of the job.
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8) xerox the nameplate news of the water heater ought buy precise replacement parts. It used to exist best ought cost over the old component although comparison ought the new element. Both the upper and lower elements are the same.
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9) Install the gasket above the element.
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10) It is no indispensable ought wrap Teflon tape or ought employ pipe dope above threads of the new element(s) unless the new component specifies the employ of it (especially if the replacement component has a gasket).
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11) earn the component into / above the opening at the tank with the bolts over the flange or threads above the element. invent definite the component is snugged tightly against the tank opening, otherwise water will leak out while the tank is filled and below pressure. it will exist best ought tighten these bolts the manner lug nuts above a tire are tightened - one nut, then the opposite nut, quote although needed. conduct no at tighten.
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12) invent definite the nearest warm water faucet is cabin vacant and vacation filling the water heater by opening the chilly water furnish valve. at first, unique stand will exist heard escaping out of the warm water faucet. although the tank continues ought fill, the warm water faucet will sputter stand and exist followed by foul water. bear fill the tank until the eliminate water from the warm water faucet runs clean and without sputtering (steady river of water) .
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13) finish off the warm water faucet.
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14) check although proof of water leaking from the new element(s). Tighten although needed ought recess the leak and sweep dry. quote although necessary. Any leak that can no exist stopped will appeal disassembling and cleaning the tank opening and component ought assure a 100% seal while reinstalled.
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15) mingle wires ought heating element. The heating elements have ought exist completely submerged at water ago applying power. Failure ought completely fill the tank preceding applying energy will arise at instant heating component burnout and will appeal replacement - again.
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16) employ energy ought the water heater.
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17) ought block water hammer, ruin vacant the warm water faucets at the family ought rent the pipes ought slowly refill. vacation with the lowest even faucets and profession up ought the highest even faucets. Optionally shift shower head(s) and aerators from descend faucets and spray heads ought block sediment from clogging them.
3. Replacing Controls
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1) assure energy ought water heater is off.
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2) The tank does no lack ought exist emptied ought substitute the controls.
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3) identify wires and respective terminals. label the terminals and the wires by either 1) writing numbers above masking tape and employ ought the wires and terminals, or 2) employ color coded tape ought wires and terminals, or 3) other identifying means, ago disconnecting.
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4) Controls are held at put and pressed against the tank by a fountain steel clip. no screws are used. ought shift the controls backward removing wires, arise the steel retaining "fingers" above both sides of the fundamental away from the tank slightly and slip the controls out. Excessive constrain above the fingers can ruin them and block the controls from seating properly. A poorly seated fundamental prevents it from properly detecting tank temperature, although it relies above corporation physical encounter with the tank although fever transfer. Removing the controls from a warm tank and retesting will ensure tank temperatures were no causing a conventional cutout.
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5) xerox the nameplate news of the water heater ought earn precise replacement parts. It can assist ought cost over the old controls although comparison ought the new controls.
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6) sweep the tank surface that the controls contact. shift any rust, garbage and dirt.
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7) slip the controls below the steel fingers and invent definite they are making good encounter with the tank surface.
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8) Rewire the controls based above the labels applied above the old controls.