Preparing to Troubleshoot. It’s the PCB that controls the gas valve (as well as other electronic components in your boiler). This is not the valve located on the control box mounted on the water heater but is instead a valve installed along the pipe run itself. Note the position of the shut-off valve in the open/on position then proceed to turn it off. If the pilot lights and stays lit after you've released the button then the thermocouple is doing it's job. Water heater problems that may be caused by the gas control valve include a faulty hot water heater thermostat, faulty gas valve, pilot light that won’t light, and tripped heat limiter. You shut the valve off and then use the union to remove/disconnect the appliance. Unlike components of an electric water heater, the gas control valve is entirely outside the water heater, and mounted near the bottom of the unit. This process is longer than 15 seconds when there is not any flame is identified. Check dial on combination thermostat/gas valve. Save my name, email, and website in this browser for the next time I comment. Open the drain valve and allow the tank to completely drain. The home’s gas is shut off because of this issue. To disengage the bypass system and allow water to enter the water heater, reverse the positions of the handles. A by-pass connects the two chambers, and the diaphragm position is therefore dependent on the exhaust from … If there is a leak at the union, the shut off valve can be used to shut the gas off in an emergency. It would be ideal to shut off water supply to water heater, shut off the gas on the control valve itself, and drain the water heater. I’m leaning towards the gas valve becuase if the thermocouple was faulty wouldn’t the pilot go out after re lighting? The igniter is then activated and everything goes with a flame smoothly. The stop-and-waste valve is turned on and off with a meter key, and when it is in the off position, it will automatically drain any water in the line. Water Heater Gas Valve assembly https://amzn.to/2WPId0fMake sure to purchase a replacement compatible with your existing gas valve. It is important to hold the water heater in place while applying torque to the connectors or you could cause additional damages. Gas control valves do not fail often, but it can happen in rare instances. 2. For safe operation of the water heater, the relief valve must not be removed from it’s designated opening or plugged. As you do, it asks the gas valve to adjust to provide the correct level of gas. The gas company had red tagged this; saying the shut off valves must be “below or at” the furnace/hwt input. 2018 IFGC doesn’t say that (409.5 Appliance shutoff valve) but your locality may have amendments and the gas company makes the rules. Your gas meter may be located outside your home on an exterior wall, or it may be found inside your home on an outside wall—often in a basement or utility area, such as a garage or the mechanical room where the furnace or water heater are located. Combination thermostat/gas valve set too low for desired water temperature. There is nothing in code that says that there can not be unions upstream of the shutoff. Verify the proper valve is installed The TPRV on a water heater is set to discharge at 150 PSI or 210° Fahrenheit. If the thermostat or heat limiter have gone bad, you may be able to replace only the faulty component, but it is generally easier and only slightly more expensive to replace the entire gas control valve. The valve can have different appearances depending on who did the installation and when it was installed. Check the front of the tank, and you will notice a red or black button. The gas mode thermostat conveys a signal to the heater handle circuit board which opens the gas valve. Must be a gas companies discretion to do what they want. I’ve been in more than enough furnace cabinets to know that is how it’s done. Position the valve downward and provide tubing so that High demand periods. 3. Does this mean that the control valve is in trouble? The 'Off' position on the gas valve dial only means that it will not heat the water. Any union in a gas line must have a valve in front of it. The pilot light is still on and gas from the main supply line is still on. The gas dryer that was connected to this valve was recently sold and before that the yellow valve was in north and south position. Step 12 – Finishing. Here’s what you need to know about replacing your water heater’s gas control valve. Shut the cold water off to the water heater. * NOTE: If on a well system the expansion tank should be set to the maximum pressure of the pump tank. Follow these simple ways to do it right. I was just surprised they red flagged the whole system because of this. Resideo WT8840B1000 - WT8840 Water Heater Gas Valve Control, NG - 1" Spud, 5" W.C. - WATER HEATER GAS VALVE, STANDING PILOT WITH PIEZO, SETPOINT 55-155F, SPUD LENGTH = 1", BRACKET= CENTERED, REGULATOR SETTING= 5" 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. You need to turn the inline valve ninety degrees so that it is perpendicular with the gas line. The outlet is controlled by the diaphragm position which is in turn dependent on the relative pressure in the chambers. Turn back on the cold water into the water heater. Make sure that the valve is in the off position. A first chamber has a gas inlet and a gas outlet leading to the burner of the heater. My question is: Does code require these valves to be after the 90 turn, before the 1/2" gas line enters the system? To facilitate removal should you need to change the furnace, and a hell of a lot easier tho handle pipe wrenches on the outside of the cabinet. This reacts to you changing your thermostat and turning on taps. Here is the code, you have two options: a) learn something you never knew b) remain ignorant, claiming how many millions of cabinets you have examined is irrelevant, your choice. On a gas water heater, the gas control valve contains the thermostat and pilot light controls. In the open position (gas is flowing) the handle (lever) will be parallel with the pipe, when it is closed (gas not flowing) the handle (lever) will be perpendicular to the pipe. A flow sensor notices the flame; the gas valve is closed while the system ends. The main gas shutoff valve is located near the gas meter supplied by your utility company. If the gas valve is labeled "White Rogers," there will be an orange wire leading to the piezo igniter. Turn the gas control valve on the heater clockwise to the OFF position (counter-clockwise for the Honeywell model). Check to make sure that the thermostat is correctly set. On the lower front of the water heater locate the combination gas control valve/thermostat. When this occurs, gas begins to leak. Your water heater has a thermostat, usually attached near the bottom of the water heater. If the pilot goes out when turning the knob you turned the knob the wrong way. Turn the water heater's gas valve switch to the "OFF" position, wait for a few seconds and then flip the switch to the "ON" position to reset the system. I’m looking at two gas shut off valves - one on the furnace input and one on the hot water tank input. These valves allow you to stop the flow of gas to your dryer, oven, furnace, water heater or gas fireplaces to make repairs or new installations without cutting off gas to your entire home. Newer models may have wires connected to the gas control valve. BTW, the Water Heater has the same install, union before the valve if you look closely. The issue here is not whether or not there is a second union inside the furnace (which we cannot see). Turning the water heater gas valve to off is not the place to do this. Looks like this -. Most service valves are single-lever ball valves; again, handle parallel to the line means gas is flowing, perpendicular means it’s cut off. To find a water heaters’ gas shut off valve look for a single handle valve that would usually be located at the bottom of the unit about a foot or two out. He didn’t say anything about the union. If the water heater was off for a while, the control valve shouldn’t be hot to the touch.