Reliance water heater gas control valve 100112336 trade number WT8840B 160 Degree F 1" Cavity made by Resideo

Fit and works perfectly for my State model GS640YBRT 300 natural gas 40 gallon water heater manufactured and installed in 2011. This Honeywell WT8840B1000 replaced the original Honeywell model WV8840B1042. In 2019 mine began to leak dribbling water from the bottom of the Honeywell gas valve itself. (Bad design Honeywell! This should never happen!) Replacing mine is just like the YouTube video others mentioned by searching: Water Heater Gas Valve Replacement. See the Q & A section and other reviews. Here's my helpful tip. The larger gas line to the burner was unbelievably tight. The whole valve flexed where I though it would break off at the part that screws into the tank, even when trying to counter by pulling the gas feed pipe on the opposite side. Solution was to gently wedge in a 5/8" thick piece of wood behind the valve against the tank. In my photo I'm holding the wrench up where the line was attached (loosen by pulling the wrench toward me). Also in the photo I cut fingers off a (blue) disposable glove and put them on the pilot and burner lines to keep them clean. Second photo is old and new valve side by side. There was a crack in the plastic sensor tip responsible for the leak. Newer improved model has metal tip. I used open end or adjustable wrenches for all the fittings. Used vice grip and robo grip pliers for removing the gas feed pipes. Test for gas leaks with soapy water in a spray bottle. Not too difficult for a do-it-yourself person. I took my time working at a slow steady pace, a few hours. The YouTube and included instructions were very helpful. I'm delighted and saved hundreds. Remember to cut off the gas feed valve and drain the tank first.

Replaced Honeywell Gas Control Valve that was flashing 5 times, indicating a bad temperature sensor in the tank. The old model just had a plastic cover where the temperature sensor is located, the new one has a metal jacket over it to protect it. Just check the chart to make sure you are replacing and ordering the right part. Original Honeywell part WV8840B1041, replacement part WT8840B1000, 1" insulation tank. The new light blinks white, does not say Honeywell on the part, but looks 100% like original. I recommend threading a 4" or 8" nipple into the gas supply opening to help provide leverage when unscrewing it from the tank.Additionally, if you are getting the 5 blinking dots, indicating a bad sensor, you can fool the valve while you wait for the new one. Turn temperature knob off, disconnect either the red or white wire until the unit stops blinking. Reconnect the wire, light pilot. Once you have the one blinking light indicating a good pilot, turn temperature knob to desired heat setting. The burner will fire up and heat water to desired temperature and then the sensor will trip out again. You can do this for a day or two while you wait for your new part to be delivered.I recommend draining the tank fully, it's just easier, but takes more time. You'll need an adjustable wrench, maybe a pair of long nose pliers. And of course, pipe plumber's tape for the threads screwing into the tank and maybe some pas pipe plumber's tape (yellow) for the gas line. The total time is about an hour, most of that was waiting for the tank to empty.

For the record, I am not being compensated in any way for this review. I'm just happy to have hot water again after more than a week of cold showers, and want to pay forward my gratitude.This unit (Honeywell WT8840B1000) replaced my old WV8840B1042, which was throwing a "5 flash" code (Temperature sensor failure). The water heater is a 40 Gallon Whirlpool N40T121-403.Using a YouTube video titled "Water Heater Gas Valve Replacement", I was able to install this unit by myself in about 90 minutes. Difficulty level 4 on a scale of 1-10 (10 being most difficult) for a person with moderate familiarity with water heaters.Kudos to Amazon and the U.S. Postal Service. This unit arrived TWO days ahead of predicted delivery. (perhaps they know that people who buy items like this are typically in a bit of a jam? We sure were. We'd been through a week of cold showers.)I write this just a couple hours after installation and am very happy. The unit works perfectly, and MUCH cheaper than buying a whole new water heater. We have hot water again! A warm shower... one of those things you don't appreciate until you CAN'T have one.PHOTO: The new unit after installation. The old unit sits beneath.

easy install. fixed my pilot not staying on. got my hot water back on.

Will change this review to a 5 star if customer support can assure me the issue I had doesn’t happen to the next person.You should not have to open a new product. After I swapped the part out I was still getting the temperature sensor failure code 5 error.So I pull out the entire bottom of the tank clean and scrubbed every surface with wire brushes and tightened every cable up.I started to process a replacement with Amazon so I decided to try something I found in a Reddit post and swap the board out.Opened the new part and found out that a sealed new product wasn’t assembled all the way. The temperature sensor wasn’t plugged into the board.3 hours on something that should have taken 45-60 minutes…Quality control should have checked this.For everyone else reading this. If this happens to you check and make sure the temperature sensor is plugged into the board. Some people call it a thermistor.

This water heater gas control valve works as expected and is an exact replacement for the OEM. It's easy to install and easy to configure.

I thought I needed new water heater but after some research I purchased this and it has worked perfectly for over a year now.