That chart requires exact numbers to get exact resistance readings. 104 items. He has 22 years of experience in the plumbing and HVAC trades, and has a bachelor’s in business and economics from Thiel College. If you have a Honeywell gas valve on your water heater, and you find you have no hot water, this may be the answer to your problem and the easy fix. It’s composed of serveral thermocouples connected in series to create roughly 350 mV of energy. Honeywell HumidIcon™ combined humidity/temperature sensors & RH absorption-based humidity sensors. Anthony Pacilla is a registered master plumber for McVehil Plumbing in Washington, Pennsylvania. 5 – Replace Gas Valve This indicates a sensor failure and the gas control valve must be replaced. That sounded easy. Viva DIY! ... Honeywell Temperature Sensors; Honeywell Temperature Sensors Honeywell Temperature Sensors. Along with straightforward management software, their products adapt well to your indoor climate demands. Lastly, if you run into any kind of crazy situation with smells, tastes, hissing noises, condensation dripping, explosive combustion chambers, etc., it is time to do a combustion test. Trade Water Heater Controls APPLICATION The WT8840 Water Heater Control is designed for use in Standing Pilot applications using an immersion well for water temperature sensing. You just need to turn on the thermostat to the heat position. Do what you need to do to disassemble the valve but leave the sensor plugged into the back plate. Verify FVS sensor resistance ~ 9KΩ -45 KΩ 3. I checked that AO Smith Gas Water heater in the laundry room right away. I first tried resetting the module by turning it to off and re-start the pilot light by turning the dial to “Pilot”, holding down “Pilot” and push the spark igniter. So far I have covered initial troubleshooting steps, specifics on diagnosing whether something is a water tank problem or a gas control issue, and the testing of thermocouples, piezos and pilot light issues. Placing WiFi Water Leak & Freeze Detectors near the repeat offenders — sump pump, water heater, washer or sinks — can keep you up-to-date on unwanted water activity and give you an opportunity to act. Original unit had plastic water temp sensor, new one has metal temp sensor… Sorry got a phone call. 60 minutes: No go. Reset gas control valve. What else could it be? I just saved $110 (Walmart’s price) for the module and enduring days of suffering through cold showers and complaints from my family members. Aquastats. The author provides some more troubleshooting and repair tips in the final installment of this four-part series. If the unit doesn’t come on and still codes, then you need to take the gas valve apart. If it finds a fault, it will shutdown. Attorneys working with ClassAction.org have reason to believe the plastic temperature sensor, which is inserted into the water heater and gauges how warm the water is, contains a defect that allows a pin-sized hole to form. This means “Normal Operation.” We’re back in business now. If you get a continuity reading, then it is good. 4.5 out of 5 stars 890. See “Lighting the Pilot / … The first thing to do to solve the Honeywell thermostat troubleshooting is by testing the heat. Then I took a sheet of aluminum foil (an electricity conducting material) and touch all the various solder joints (silver-looking blobs) especially the big capacitors, which are the energy storage devices. the meaning of this is temperature sensor i mean code 5 mean temperature sensor failure since yesterday the water is not consistent,but this morning when i increase to high temp,it come to normal operation. What a nifty device! commercial products. !” Not good. And confirm a good connection. Immediately, the burner turns on and we have a lift off! Zero - Controls off, pilot out normal operation would be one flash. Often blamed on sediment in the tank, the 4 flashes is one of the most common problems with the Honeywell gas valve. Locate the hot surface igniter and look for a spark or glow there. Honeywell WT8840A1000 - WT8840 Water Heater Gas Valve Control, NG - 1" Spud, 4" W.C. - WATER HEATER GAS VALVE, STANDING PILOT WITH PIEZO, SETPOINT 55-155F, SPUD LENGTH = 1", BRACKET= OFFSET, REGULATOR SETTING= 4" W.C., GAS TYPE=NATURAL GAS The WT8840 series is the Water Heater Control for trade use to replace WV8840 valves used in AO Smith and Bradford White Water Heaters. No go. The gas valve is not getting the signal. So I removed the PCB (printed circuit board) from its housing by unscrewing the torx screw and snapping the PCB from the housing. Temperature & humidity sensing Use to detect temperatures that can freeze pipes, and humidity that could damage valuables. Get Residential Plumbing articles, news and videos right in your inbox! Clean the burner, the burner assembly, the orifices, the burner ports, the air shutter (if it has one), feed line, venturi (if it has one), pilot assembly, etc. The sensors have the ability to record and log your humidity and temperature of the area you are monitoring. Filter. The water heater is a 40 Gallon Whirlpool N40T121-403. CS8840 pilot assemblies are Clear 4-blink fault code on Honeywell water heater gas valve. Hard lockout to be cleared when the power is manually cycled, the control dial is rotated through the HOT setting 7 times within 30 seconds and the resistance of The Honeywell gas valve went into “High Temperature Shutdown” mode. If you don't want to bring your iPad into the bathroom, we can send you a magazine subscription for free! Look up the manufacturer’s chart for sensor resistance at various temperatures and figure out what your resistance reading should be. Drain about 4 to 5 gallons of water out of the drain valve at the bottom of the water heater and throw it out. This unit (Honeywell WT8840B1000) replaced my old WV8840B1042, which was throwing a "5 flash" code (Temperature sensor failure). One of the most basic skills a plumber should have is repairing a tank-type water heater. The problem is that the microcontroller inside the unit remembers the last “over-temp condition” and would not forget it. After a minute or so, the LED started blinking once and paused and blinking once again. Please enable JavaScript to view the comments. This was 10pm two days ago. This leak sensor is great for stopping water or flood damage from water heaters, sump pumps, washing machines, dishwashers, sinks or toilets. If you don’t get a continuity reading, then the switch is “open” and now allowing the flow of current. but radiators are cold and/or taps are running with cold water. will shut off the water heater if the water temperature becomes excessive. 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