Reliance 9001954-045 Upper Electric Thermostat with ECO, Pack of 1, Black

Restored my hot water heater to like-new heating.

easy to install

Reliance W10A 9001954-045 Upper Electric Thermostat – WH10A Our water heater’s upper electric water heater thermostat had WH10A printed on it, so this appeared to be and was, the exact replacement part. Sears, Westinghouse, State Select, and many other brands use this as the upper thermostat – and a part labeled WH9 or WH9-6D (long shaft for exposed control knobs) for the lower thermostat. WH10A operation: electrifies the upper heating element until the set water temperature is reached; then transfers all power to the bottom thermostat and element. WH9 operation: electrifies the lower heating element until its set water temperature is reached, then turns off. Set the dial on each thermostat to the approximate same temperature, typically between 110 and 140 according to preferences. Note that you can’t always rely on the markings on each thermostat and will need to use trial and error. An infrared thermometer (point & shoot type, with a digital readout) is very useful in verifying water temps, and can instantly show the temperature of tap water or of the steel outside of the hot water tank next to the lower thermostat (when the thermostat’s cover is off). Setting the WH10A thermostat midway at “B” resulted in 120 degree hot water, which suited us. Only one heating element is electrified at a time, otherwise, the current draw would exceed 7200 watts and (on many water heaters) the circuit breaker would trip. 7200 watts is the maximum capacity of a 240 volt, 30 amp,10 gauge wired, circuit. For example, both elements on with our water heater would draw 9,300 watts. Typical water heater failure symptoms include: 1. Water doesn’t get sufficiently hot: ... one or both thermostats is set too low; or ...upper thermostat transfers power before the set temperature is reached AND the lower thermostat shuts off prematurely (i.e., both thermostats are defective). 2. Water is scalding hot: ... a defective thermostat locks on power to its corresponding heating element; or ... one or both thermostats is set too high. 3. Water never gets hot: ... the upper thermostat fails, so the top of the tank isn’t heated; and power is never transferred to the lower thermostat / element; or ... the upper heating element failed; or ... both thermostats are set too low; or ... the 220 volt circuit breaker has tripped (see your service entrance panel); or ... circuit breaker wires are loose; or ... there are loose / burned-out thermostat or element wiring; or ... a thermostat reset button tripped (Note: the red reset button or 'high limit control' or Energy Cut Off / ECO will cut off electric power to the entire water heater). 4. Water temperatures wildly varying – happens if there is inconsistent thermostatic function 5. Low volume of hot water: ... the upper tank heats properly but that thermostat fails to then transfer power to the lower thermostat / element, resulting in hot water in the top of the tank only; or ... the upper thermostat is working properly but the lower thermostat or lower heating element failed; or ... a thermostat is set too low. 6. Hot water recovery rate is low: ... the upper thermostat transfer of power to the lower element is locked on; or ... the lower heating element failed; or ... a thermostat is set too low. Upon a suspected malfunction, try pressing the red reset button on both thermostats as a stop-gap measure. If you hear a snap sound (reset of its thermal disk), or it won’t stay pushed in, you may need to replace that thermostat. If the water is scalding hot and the thermostat’s temperatures are set properly, switch the breaker off until the water cools, turn it back on when it drops to 120 degrees, and keep switching it on/off while waiting for parts to arrive. Replace the small pieces of insulation covering each thermostat only after final testing. There can be water heater issues other than those listed above, not counting outright leaks. An unwired heating element is shot if an ohm meter shows no continuity between its terminals. Without removing any wires, you can also test an element with the heater’s circuit breaker on. Use a volt meter to measure the power at a heating element. When electrified, the reading should be 220-240 volts AC and that area should get hot. If the tank adjacent to the element doesn’t warm up (use an infrared thermometer), that element is likely dead. Remove the heater’s thermostat/element cover to test using a volt meter. Be very careful, so you don’t get shocked. I gave it 5 stars because the W10A thermostat I received worked perfectly. The lower (WH9) thermostat on our water heater was also defective – it shut off at 110 degrees even on the maximum setting -- so I replaced that thermostat also. In any case, these parts are relatively inexpensive, especially compared to hiring a plumber or getting a new water heater, so consider replacing both thermostats if either fails, just in case. More... - 240Volt water heaters have 2 hot wires and a ground wire. Each hot wire is called a leg. Each leg is 120 volts with 240 volt potential when both legs are connected. - Thermostats turn off only one leg in the 240Volt circuit. The other leg puts live power to a heating element at all times, but draws no power because it’s only ½ a circuit. - Each element should read 120Volts between the element and the grounded steel tank (or a ground wire) if the circuit breaker is on. - When a thermostat turns ON, that connects the second leg to the element’s first leg, and the element turns ON and heats. - In some cases, a heating element can crack or short. In many cases, a short will trip the electric panel circuit breaker. - If the crack or short is far enough along in the element, the resistance may not cause breaker to trip. - If an element continues heating, and will not turn off, you’ll have runaway heating, and the temperature/pressure relief valve could open, releasing water – or the ECO (energy cut-off) reset will trip, or water will be hotter than usual.

Was a perfect match to original

Replaced a thermostat on my AO Smith water heater that was causing the circuit breaker to trip. So far, this has worked perfectly. The only negative is that the degree markings aren't very accurate, but I think that's true of all of them. I set it a little hotter than 120F, but water temps were only ~ 113. I just turned the temp knob up a little bit, so no big deal. Before ordering, make sure this matches your water heater. Some AO Smith heaters use a large thermostat. This won't work in those, and the larger thermostats won't fit in heaters that use this one.

I had a problem with the water heaters internal breaker tripping repeatedly and having reset it almost daily...which made for a number of cold showers in the middle of winter. I ordered this replacement thermometer...installed it per the included directions and have not a problem in the almost 3 months it's been installed. The instructions are super simple and easy to follow. i was worried about replacing the wires in the wrong place, but they are all color coded (I'm very new at the home owner do-it-yourself-ing) and I didn't have any issues. Sure beats spending over a grand to replace the whole heater.

Exact replacement for 12 year old A O Smith water heater.

Perfect replacement for my A.O. Smith water heater thermostat. Mine was made in USA

I highly recommend this water tank thermostat to anyone looking to improve their hot water system. It’s reliable, efficient, and has made my home life so much more comfortable. If you’re tired of temperature fluctuations and want a hassle-free solution, this is definitely the product for you

Easy to install. Works well

The Parts were Excellent and Did the Job Thanks for Posting them here on Amazon. I was so Happy to find exactly what I needed to fix my Hot water Tank which by the way works Fantastic.

It's like the one I had Easy to install I have HOT WATER again!! YAY

Our heater broke; checked the model number and found this item on Amazon; bought it, which took 3 weeks to prepare and ship from NY, USA to Canada. The shipping package was a bit rough; no box protecting the product just a regular shipping brown bag. but luckily the product was ok. Installed it and our heater was working again.