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Honeywell

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

  • Based on 1,788 reviews
Condition: New
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Availability: In Stock.
Fulfilled by MaxWarehouse
Arrives Monday, Sep 21
Order within 22 hours and 41 minutes
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Features

  • Temperature ratings: ambient-- 0 c to 60 c

Description

The Wt8840 Series Is The Water Heater Control For Trade Use to replace WV8840 valves on AO Smith water Heaters. It Is Designed For Use In Standing Pilot Applications Using An Immersion Well For Water Temperature Sensing. Made in United States. Manufactured by Honeywell.

Material: Metal


Brand: Honeywell


Item dimensions L x W x H: 7.7 x 5.9 x 5.4 inches


Exterior Finish: Brass" or "Stainless Steel


Inlet Connection Size: 1 inches


Inlet Connection Type: National Pipe Tapered


Outlet Connection Type: Flare


Maximum Operating Pressure: 5 psi


Number of Ports: 2


Outlet Connection Size: 1 inches


Brand Name: Honeywell


Model Number: WT8840B1000


Number of Packs: 1


Global Trade Identification Number: 38


Unit Count: 1 Count


Manufacturer: Honeywell


Manufacturer Warranty Description: No Warranty


Number of Items: 1


UPC: 085267605038


Included Components: Thermos


Item Weight: 2 pounds


Number of Pieces: 1


Set Name: WT8840B


Manufacturer Part Number: 100112336


Exterior Finish: Brass" or "Stainless Steel


Inlet Connection Type: National Pipe Tapered


Outlet Connection Type: Flare


Maximum Pressure: 5 psi


Number of Ports: 2


Thread Size: 0.5 inches


Thread Type: National Pipe Tapered


Connector Type: Threaded


Valve Type: gas control valve


Item Dimensions: 7.7 x 5.9 x 5.4 inches


Inlet Connection Size: 1 inches


Outlet Connection Size: 1 inches


Size: 7.7 x 5.9 x 5.4 inches


Material Type: Metal


Specification Met: Yes, meets relevant industry standards for gas control valves in water heaters


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, Sep 21

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Top Amazon Reviews

    • It works and I have hot water again!
Review Image by Paul L.
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. ... show more
Reviewed in the United States on December 2, 2018 by Paul L.
    • Fits and matches original. 100%
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. ... show more
Reviewed in the United States on March 20, 2024 by J. Batchelor
    • Perfect replacement for WV8840B1042
Review Image by Joe in Virginia
Review Image by Joe in Virginia
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. ... show more
Reviewed in the United States on August 16, 2019 by Joe in Virginia
    • Buy it new
I installed it just to find out it was defective. The control know would not turn as if it was seized.
Reviewed in the United States on August 15, 2026 by Shan
    • Great gas valve
Water heater pilot would not stay lit light on gas valve not on tested thermopile and it was good bought this gas valve and installed , water heater is back up and working
Reviewed in the United States on April 19, 2026 by Amazon Customer
    • Works. Nut and ferrule are not right size. Fixed 5 code error, but gave 7 code. Was able to fix.
Replaced my Honeywell WV8840B 1042 series with this. The Honeywell did not want to install squarely at first, which if not caught can ruin threads. The nut and ferrule that comes already in the Honeywell for the pilot gas line would not work on the outgoing gas line; the nut and ferrule were both too big. Be sure to have a backup or use previous. So far this is working great. I had to reset the Honeywell, because it gave me a error 7 code. I panicked at first, but then found that you need to turn it off> turn knob from low to just past high seven times in under thirty seconds to clear error. The only thing I do not like about this piece upon firing it up is that it takes far longer to ignite the pilot than the previous version I was using. It takes many, many more attempts. IF this items craps out I'll be sure to throw a fit (I just went a week without hot water) and then reply back to here. ... show more
Reviewed in the United States on July 12, 2019 by 0909
    • Good replacement
Review Image by mikeworldtraveler
Review Image by mikeworldtraveler
Review Image by mikeworldtraveler
Review Image by mikeworldtraveler
Same situation as others and needed a replacement. Have an AO Smith water heater about 8 years old. Honeywell controller showing five blinks indicating temperature sensor failure. The replacement took about 1 hour. I turned off the gas in the morning and started draining went I came home from work. Started taking the gas pipe apart starting at the union. That was the hardest part and I suggest using proper pipe wrenches. I used pipe dope and tested gas leaks. Nothing bubbled and no gas smell. Startup was the same. Only difference is the white light vs red in the original. Water has been staying hot and burner starting and stopping properly. There are YouTube videos that helped explain the steps you can see. Hoping this control valve lasts longer. Next is to check the anode rod again next year and drain. ... show more
Reviewed in the United States on May 1, 2024 by mikeworldtraveler
    • Exact match
Perfect fit. Plug and play. Hot water again !
Reviewed in the United States on February 20, 2026 by Bill D

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