Rheem Hybrid Water Heater Gen 4 EVAP Thermistor Sensor ET sensor replacement location

Thanks for posting your video! Our Rheem Gin 4 hybrid water heater has worked well for 5 years but recently began exhausting noticeably warmer air into our kitchen and was running longer to produce the same amount of hot water. I noticed that the displayed evaporator temperatures were implausibly high. I called Rheem hybrid water heater support who decided that a faulty evaporator thermistor was likely to blame, a common problem. Support sent me 2 replacement thermistors (1 spare?). I assumed that the evaporator thermistor would be easy to replace, but no instructions were included with the thermistors. When I found this thermistor, no replacement procedure was obvious to me. This video doesn't show how the replacement thermistor was installed which seems almost impossible through the tiny space above it. I called Rheem support again to ask for instructions for removing the top part of the water heater cabinet surrounding the heat pump hardware which would have provided good access to the evaporator thermistor. I was told that this wasn't recommended and wasn't necessary because the thermistor could be replaced from above. Obviously, the support agent had never replaced a Gen 4 evaporator thermistor. I decided that the only way to replace this thermistor with a good result was to cut an access hole through the side of the cabinet. Fortunately, our water heater has some space around it, so I was able to cut a neat 5" x 5" access hole using several Dremel cut wheels. Replacing the thermistor was then very easy to do. I was also able to insulate an uninsulated spot on the refrigerant tube between the thermistor and evaporator where condensation has been occurring resulting in some pooling of condensate on the top of the water tank below the tubing. After replacing the thermistor, I painted the exposed edges of the access hole with appliance paint to inhibit rust in our humid, salty environment and covered the access hole with a 6" x 6" piece of aluminum flashing attached to the water heater cabinet with double-sided tape. It actually looks pretty good and is on the side of our water heater where it isn't too visible. Anyone who needs to replace the evaporator thermistor should consider doing what I did. It seemed like a radical solution at first, but this thermistor isn't in the evaporator air handling area so I could have left the access hole uncovered without causing any problems.

[@soteriology400]

I’ll be getting a hybrid water heater from Rheem installed soon. Nice to see your comment, very helpful in the future. 👍

[@9496TULL]

Got the same code last week on mine. It’s around 2 years old. What a bunch of bull for this expensive water heater. Haven’t called Rheem yet. I will replace it myself when I get some free time Thanks for the video

[@abbycantalk9251]

Rheem sent me a video of how to do this, but I couldn't find the right location for the EVAP thermistor until I found your video. Thank you so much! Why on earth they have such a tight space for the thermistor is beyond me. I'm a woman with small arms and I still could barely get my arm low enough in that tiny space to cut their zip ties.

[@GriesingerM1]

Rheem sent me the wrong video. Yours showed me where the evaporator sensor was for my Hybrid Water Heater. Wow it was tough clipping all those zip ties, had to use a mini hack blade for the last one because pliers couldn’t reach that far. I wish they made it more serviceable, I’m still not sure it is on snug enough and covered properly with insulation. They should ship some of that sticky goop and replacement insulation with the parts.

[@RobertSokol-s7w]

My hot water heater is less than a year old and had this thermistor go out. I even had the extended warranty. Rheem told me that they have no technician in Kansas City, even though there are around 10 or more Rheem HVAC businesses in this area. When I called the extended warranty they told me that since I am under the OEM warranty, I must deal with them. Rheem sent me the part and I ended up fixing it. Very disappointed with Rheem.

[@richardjordan6205]

@@RobertSokol-s7w It's the way most systems will be, windows, HVAC and roofs. But you can get extended through Home Depot for windows and heaters. Gaf will back their product plus install but it's not cheap. So we just have to realize these new technologies are made cheap and manage with extended coverage.

[@mikebayus8355]

2/11/24 Ya had to change my EVAP sensor not to bad to get to it. Rheem supplied the parts.

[@francam853]

Actually, you appear to be replacing the Discharge Temp Sensor, Code 106.

[@richardjordan6205]

The title is correct and the part they sent matches the title so regardless of what I mentioned, this video is spot on with regards to the location of the evap sensor.

[@JoePalumbo221]

Just saying... That there's a better way to access the thermistors. The top half slides up taken 5 screws out.

[@delmarstewart]

I have an issue with this same rheem hp wh. At 2 years the one sensor failed. I called and they sent three sensors and tell me to replace them. Parts are free bit 225.00 for a plumber to replace them. But i question why they sent me three sensors and told me to replace all three. They are all white wires as well and not the colors in their diagram or the video they sent. I smell another class action lawsuit brewing if they don’t figure this out.

[@richardjordan6205]

Hi Delmar, the sensors are easy to replace, the most difficult is the thermistor and this is why I posted the video, none of the videos show the exact location of this sensor. $225 for this is a rip, DIY is the way to go.