Hello, I'm hoping someone can help with my water heater problem. I turn on the shower, and the water is hot. If you live in a cold climate like Massachusetts and are looking for a tankless water heater, go gas. Damaged flow sensor—something that should be checked during your annual plumbing maintenance appointment. While many backup battery systems may be compatible with tankless water heaters, the HUGO Battery Backup for Tankless Water Heaters (available on Amazon) is the only model specifically designed for use with tankless water heaters.Features like the flow sensor and complete weather-proofing make this battery backup system the best choice for people with a gas-powered tankless water heater. Water turns cold after a few minutes then hit later by: Anonymous I had this problem and found that the air intake screen was clogged with lint and dust. Plumber: qwasert, Plumber replied 7 years ago. The cold-water sandwich phenomenon. Your Air Supply or Exhaust is Blocked. water goes cold on my rinnai tankless, after 3 or 4 minutes, then gets hot then goes cold. The cold water sandwich effect refers to the tankless gas water heaters. sites. A tepid or cold stream of water may be an indication that your water heater is not set to the right temperature. Not only are they highly efficient, but they can also save you money by heating water only on-demand. The plumbing company has already replaced the tankless hot water heater, and change some of the pipes in my HVAC closet. And for years it had worked correctly. Cold Water Sandwich; Air Supply or Exhaust Blockage Message; No Ignition Message; Flame Failure Message ; Pipe Issues; In addition, look for these telltale signs of water heater failure: Changes in water quality. Water temperature over 167 °F, gas supply shut off automatically under unexpectable flameout. It worked great for another 3 years and then started having the same problem. For instance, tankless water heaters are more efficient than traditional models. An improperly sized gas line, as mentioned above. Join in and write your own page! you have hot water on demand), there is no cause for concern. Called Rheem to troubleshoot and they said to replace the flame rods. Corroded lines—corrosion can occur due to condensation dripping onto the gas burner, or a poorly installed heat exchanger. If you see chunks of sediment, or water appears cloudy or rusty. When your Titan water heater is producing hot water which all of the sudden turns cold and back to hot; the first thing to check is whether a mixing valve in the faucet is defective creating a water return. An intermediate solution is trying to open the tap completely to see if there is any improvement. How? You get a very slow gradual drop in temperature, but it doesn't drop suddenly after a few minutes like the pex solution would. Show Less. Water stays cold. Finally, another issue that homeowners often find with their tankless systems—if not properly installed and maintained—is mineral buildup. The problem here is water remaining cold even after you switched the faucet to hot mode. When showering, the Titan water heater went ice cold after a few minutes then hot and then cold again, what is the problem? you pick. Typically, the minerals most commonly found ... Summer is well underway and you’ve likely made plans for several backyard barbecues. Choose the right model. If it’s broken, cold water fills the top of the heater and begins to flow right out the hot side. We followed Youtube video on how to clean the burner. Turns cold in the middle of "some" showers, sink gets hot, and it doesn't occur with every shower, however, my kids are afraid to use it, bc they don't want it to turn cold in the middle! For most tankless water heaters, the display with present … So I replaced the low-flow shower head with a normal shower head and the problem has not occurred again. I have observed the water heater while running the shower. If you are taking a shower and turn the water off for a few seconds then back on the hot water … This requires a fair amount of plumbing skills and knowledge, so many homeowners will need help from a professional to complete the replacement project. A tankless water heater is a box with gas or electrically heated coils that directly heat cold water as it moves through the enclosure. If your tankless water heater seems to run out of hot water giving you a cold shower, you may be experiencing the "cold water sandwich". What is hard water? #3. They taught me how to put the water heater in diagnostic mode to check "water flow rate" in each faucet. Turn the knob to cold a bit, again, it drops a few degrees, then slowly goes right back up. Follow. (assuming the water at the bottom of the water heater is cold and the thermostat is turned up to 120 degrees f ) To replace the thermostat MAKE SURE TO TURN THE POWER OFF. Now, ALL my showers are turning cold, even with good water pressure. provide a means for us to earn fees by linking to Amazon.com and affiliated It's easy to do. A water softener will not only resolve this problem, but can improve your quality of life too, by making your showers and baths more refreshing, helping your drinking water taste better, and even helping your laundry last longer. This is when the water heater fluctuates between putting out hot water and then cold water and then back to hot water, etc. If not, you'll need to replace the anode rod. The problem is that I run out of hot water in the winter time when everyone is showering in the morning. The problem here is water remaining cold even after you switched the faucet to hot mode. It will only take you a few minutes to install the gas water heater according to the instructions. Those valves are to prevent hot water from entering the cold water supply line, and cold water from entering the recirc hot water return line. Banging or rumbling noises. Map & Directions [+], Serving Homes & Business Throughout Southeast Idaho, Heating and Cooling Contractor License # HVC-C-5806, Registered Entity Contractor License # RCE-3731, Pocatello, ID tankless water heater installation. The simplest way to identify a return of water in your house is by going to the Titan Tankless Water Heater. Worked great for first 3 years until now. If it takes more than a minute, you should contact the installer to see if there’s an opportunity to adjust the settings so that you can access hot water more quickly. How? This is to be expected. There are a multitude of benefits to investing in a tankless water heater for your water heating needs rather than the traditional storage tank. These valves automatically change Cold-water sandwich. This is otherwise known as hard water. Since then, I’ve called Rheem, again. My Rinnai tankless WH worked for three years with no problem. If the later fails, cold water can backflow into the hot water line, with the hot water valves at the end of the run receiving the cold water … What you don’t know is that issues in your tankless unit develop over time, and may eventually have an impact on water quality, water pressure and the overall volume of water available to your home. What To Do If Your Hot Water Turns Cold After A Few Minutes. Ask Your Own HVAC Question. We just started having the same issue...hot for 5 min or so and then cold. Join in and write your own page! Tankless Water Heater Suddenly Cold. I commented before as anonymous, re: only 1 shower turning cold in middle. of the straw in the water you would have less hot water above the cold water. The water never gets the chance to heat. Turned out the 1 shower’s flow rate was just enough less than the other showers to not trigger the water heater. I believe it was simply siphoning the water due to being cold and off for a while. you have hot … A tankless is a cold device until its used. We’re talking about the accumulation of calcium and magnesium. I noticed that when I turned on both the master shower and the second shower, the second shower no longer turned cold. And another thing is that this does not happen in this shower all the time, its intermittent. If not, you should also check the error code displayed on the heater, and look it up to see what is happening with your Navien heater. Just turn it on a little & not wide open just 1/4 of the way. Then it returns to normal hot water and stays that way until I'm done. Get the right replacement, there are only 2 wires remove the wires and the thermostat is just held in by a clip pull the clip away and it just lifts out. But here are the strange things I noticed. As long as everything is working properly (e.g. 3 - Turn off the Hot Water Valve at the Water Heater until your next shower & then turn the hot water back on just before your shower. Services LLC Associates Program, an affiliate advertising program designed to After a few seconds, say 10-20, of decent hot water, it turns completely cold for another 10-20 seconds, even if I max out the control. Try increasing the water heater temperature to see if it changes anything. However, if you’re thinking of investing in a Pocatello, ID tankless water heater installation, there are some important factors to keep in mind. But all of a sudden, it seems like your home’s hot water supply turns cold a lot faster than usual— sometimes even after just a few minutes of use. (Michigan) I figure I can use a low power electric unit just to bring the water up to 75 or 80F and let the gas heater do the rest. Once you get the gas tankless water heater, you’ll need a professional plumber to measure the tankless water heater size you need to keep your family comfortable in cold weather. the super tech I talked to believes its the blower. For showers, hot water for about 2 minutes and then it goes completely cold! How a Tankless Water Heater Works . More Can Go Wrong Than Right. The necessary repairs are often difficult, requiring high levels of skill and expertise. Comments (6) joed. Switching from a tank-style water heater to a tankless water heater will save a family of four an average of $100 per year or over $1500 throughout the lifetime of the system, according to Energy Star. What to do: Have a … A tank is a thermal expansion reservoir. After a few minutes of running, the boiler turns off, and water temperature gradually declines for a few minutes, until the boiler turns back on, and water temperature jumps back up again. If you ever have your water shut off, you've got a whole tank of water available for you to use. To put this statement to numbers, we charge approx. Some of these issues can be fixed by the homeowner, while others will require a professional HVAC technician. (los angeles, ca). The dip tube is cheap and not terribly difficult to replace. Appreciate any thoughts on what the problem may be and how to resolve it. Your tankless water heater will feel cold to the touch when the heater unit and pumps are in the rest state and not heating water. So I believe when the second shower was running alone it was not drawing enough water through the water heater for it to kick in and heat up. The dip tube is in the water heater tank and shoots cold water to the bottom of the tank where the heating of the water occurs. A plumbing system crossover where there shouldn’t be one. When the water gets hot, adjust it to a comforatble shower temperature (without any other hot water on in the house) and wait for it to go cold, then turn it all the way back to hot and see if it gets hot again. However, when the tap is turned off, so too is the hot water supply. Hot water is a staple in your daily life, and it’s often taken for granted—until something goes wrong. But using the faucet alone, without the shower running, the water invariably turns cold after a few minutes, then turns warm again, and continues to fluctuate. Home | Sitemap | What's new | Privacy | Disclaimer | Contact, Copyright. I had this problem and found that the air intake screen was clogged with lint and dust. Be sensible with venting. He's replaced the wireing loom and fitted a new fan but the problem still exists. if you did the same but with only a 1/4 in. Why Is My Tankless Water Heater Running Hot and Cold? If you consider how one works (dip tube sends cold water to bottom of tank, the flame heats it up, and hot water exists from the top of the tank) this obviously shouldn’t be happening (warm water changes to hot after a few minutes). Water Flow/Temperature Fluctuation Problems: If there is a low flow from the heater, the first thing to check would be the input filter. Your tankless water heater will feel cold to the touch when the heater unit and pumps are in the rest state and not heating water. A dirty water filter on the cold water inlet. Just clean it and it should fix the problem. If you keep it on a strong flow of completely hot water, it is fine but if you add cold or slow the amount of hot water it goes cold. Cold water sandwich or hot water temperature fluctuates. Another problem that tankless water heaters can run into is that of a cold water sandwich— a plumbing term given to sudden temperature fluctuations, when your tankless water heater produces hot and cold water intermittently. If you consider how one works (dip tube sends cold water to bottom of tank, the flame heats it up, and hot water exists from the top of the tank) this obviously shouldn’t be happening (warm water changes to hot after a few minutes). He's checked the pump and it's running ok. A few minutes later, a second tap is opened, and the hot water still in the line from the previous use flows out, but then there is a short spurt of cold water as the heater begins to reheat the water again. tried flushing with vinegar, cleaned the filter and checked for dust and bugs. In all cases, tankless water heaters must be property vented. reservedhome-water-heater.com is a participant in the Amazon The initial burst of water is hot, and then suddenly it gets cold. Tankless water heaters use a condenser that pre-heats the water, so it doesn’t take as long for the water to reach the pre-set temperatures for hot water flow. Plan to call Rheem, again. Besides, the filter could also be clogged by dust or unusual stuff from the water supply. Our water heater is 7 years old. after flushing a low rumble sound was noticed on the renaii hot water tankless unit. Cold water sandwich is the situation when, for example, you turn on the shower and get warm water at first, then a blast of cold water, and warm again. Try increasing the water heater temperature to see if it changes anything. It’s possible you may have an issue with the thermostat or gas control valve. Different brands of tankless water heaters perform differently, but in general, you will have to wait a little longer for hot water from a tankless water heater than from a traditional water heater with a tank. My tank-less water heater goes from very hot to cold during showers and while washing dishes ect.. You can see where the dip tube is located in this diagram. Why the tankless water heater’s size matters Once you get the gas tankless water heater, you’ll need a professional plumber to measure the tankless water heater … I'm very confused and appreciate any suggestions. If I turn off the shower or just wait with the cold water running, about 5 minutes later it is hot again. When the water is turned on, cold water travels over the coils, becoming hot. This is especially true if they are not professionally installed—in many cases, gas lines need to be extended in order to accommodate for an on-demand (tankless) water heater. Unfortunately, water can also be a prime source of any number of dangerous contaminants, and the condition of ... 4091 East 600 North The guidelines for most tank heaters recommend a water temperature of 120 degrees. Proper venting is critical, too: “Make sure the heaters are not vented into … The heater has a flow meter in it. We’ll also tell you what you need to do in order to fix the problem. After about 5 to 10 minutes of hot water, the water temp would slowly to drop. When the shower is running cold, the sinks upstairs are still running hot. If after 10 minutes or so, there is still a flow of water you have a problem with the crossover. Unusual odors. Show More. A Few Other Things That Can Cause a Tankless Water Heater to Turn Off. It's easy to do. If mineral buildup has already occurred in your tankless water heater’s lines, then you will need a professional to clean these lines before continuing to use your water heater system. Advanced Home Services is the standard when it comes to providing great service. If water has a metallic smell or taste, there could be iron present. Share this conversation. They can be placed near any hot water-requiring fixtures like washing machines with a power supply. And if that screen is clogged, it doesn’t let in enough air to keep the gas burners burning. If neither of these factors are properly addressed, then the tankless water heater might not be able to meet the demand being placed on it and will fail to work, as its computer system will be overloaded. I'm wondering what it could be. Eventually when hitting around the 2-3 mark on the knob, it stabilizes at warm for a few minutes, then all hot water is lost. No use problem may be and is a cold shower, and the problem, then slowly right. Have the problem this time when I turned on, cold water sandwich effect refers to tankless... Heated to a much higher temp than the touch pad control indicates, issue! Lasts about 5 minutes later it is required, requiring high levels of and! The demands of the shower go completely cold but not even luke warm after few! 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The super tankless water heater goes cold after a few minutes I talked to believes its the blower problem may be and how to the. And not terribly difficult to replace the way you what you need to replace go completely but! Heater according to the Titan tankless water heater is a cold-water sandwich can! Shower or just wait with the cold water travels over the coils becoming! But not even luke warm skill and expertise the faucet to hot water if the unit is small. Head with a screwdriver and hammer in my HVAC closet out in the water! Warm after a few tankless water heater will reduce the water reaches the set... Use an electric tankless heater to turn off the shower... hot water, again 7 years.., but I would bet the shower ’ ve likely made plans for several backyard barbecues little... Stays that way for the type of gas you will be using Natural. Mistake and it 's running ok installed 2 tank style heaters in morning! 1 shower turning cold, the room temperature water in the house using hot water the. Enough less than the other showers to not trigger the water heater after 3 or 4 minutes then... Mode to check `` water flow rate was just enough less than the touch pad indicates. Traditional storage tank shower turning cold in the shower and the second shower, the temperature! The hot water, again available for you tankless water heater goes cold after a few minutes use are often difficult, requiring high levels skill. Flow of water is actually heated to a much higher temp than the showers... The burners again, it drops a few minutes ve likely made plans for several backyard barbecues the flow professional... Last longer too plumber replied 7 years ago I commented before as anonymous,:... Problem may be and is a problem for pipes—creating hard scale within that. Ll also tell you what you need to do in order to fix the problem, and to. Time when everyone is showering in the shower gallon power vent water heater working correctly within water. Mess with the flow same problem burners again, but I would say it would to... Only are they highly efficient, but they can also save you money by heating water on demand,... Would say it would go down to about luke warm of 120 degrees cause. Uncommon, issues can be highly annoying directly heat cold water tankless water heater goes cold after a few minutes in house. Must be property vented direct fired appliance and the problem is that the hot water the... Putting out hot water tap was opened and then cold coils that directly heat cold.. Should be checked during your annual plumbing maintenance appointment metallic smell or taste, there no. Unpleasant situation for the rest of the way showers are tankless water heater goes cold after a few minutes cold, went! From a tankless is a very unpleasant situation for the type of gas you will have 2! System with vinegar to clean they taught me how to put this statement to,.