The dip tube is cheap and not terribly difficult to replace. These valves automatically change Before you send out the invites, it’s best to ... Water is essential. Then the water heats from cold every time the water is turned on so the heater can not get hot enough to heat cold water for a few seconds and cold water will follow the hot water in the pipes. 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. 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. Choose the right model. I would bet the shower head is clogged up enough to mess with the flow. Cold water sandwich or hot water temperature fluctuates. This is otherwise known as hard water. Ugh. Plan to call Rheem, again. Try increasing the water heater temperature to see if it changes anything. Although uncommon, issues can arise if something isn’t working correctly within your water heater. you have hot water on demand), there is no cause for concern. Hot water is a staple in your daily life, and it’s often taken for granted—until something goes wrong. (los angeles, ca). Took the shower head off, tapped out the aerator with a screwdriver and hammer. The tankless water heater works by directly heating water on demand, as it is required. This is to be expected. When the water is turned on, cold water travels over the coils, becoming hot. Why Is My Tankless Water Heater Running Hot and Cold? So what accounts for that intermediate burst of cold water? The problem here is water remaining cold even after you switched the faucet to hot mode. What is hard water? 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. Why the tankless water heater’s size matters. Not to ice cold, but I would say it would go down to about luke warm. For instance, tankless water heaters are more efficient than traditional models. As long as everything is working properly (e.g. Show More. No one else is in the house using hot water, so that's not it. 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. This is because they are not subject to standby energy loss in the way that a tank model is. The plumbing company has already replaced the tankless hot water heater, and change some of the pipes in my HVAC closet. Tankless water heaters also take up far less room than their storage tank counterparts, and tend to last longer too. qwasert, Plumber. 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. it took a couple minutes, but went away. Worked great for first 3 years until now. Put it back on, voila... hot water, again! Turn the knob to cold a bit, again, it drops a few degrees, then slowly goes right back up. reservedhome-water-heater.com is a participant in the Amazon Try increasing the water heater temperature to see if it changes anything. A few years ago we installed a tankless hot water heater and we love it. However, we have had several house guests get ice cold showers, even after tutorials on how to adjust the temp. (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. 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. if you did the same but with only a 1/4 in. Did this, still no luck. you have hot … A plumbing system crossover where there shouldn’t be one. 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. the super tech I talked to believes its the blower. Tankless water heaters are not immune to problems. Appreciate any thoughts on what the problem may be and how to resolve it. I believe it was simply siphoning the water due to being cold and off for a while. Contact us for comprehensive plumbing services today! Open all the hot water taps. This unit is equipped with an internal freeze protection … A tankless is a cold device until its used. But if you’ve been cranking up the heat in the shower, but you still have lukewarm – or even cold – water, you may be wondering what the problem is. The heater has a flow meter in it. Ask Your Own Plumbing Question. It's easy to do. Advanced Home Services is the standard when it comes to providing great service. Oct 4, 2018 - If your hot water turns cold after a few minutes you most likely have a defective dip tube. If the tankless water heater is shutting off when someone opens or closes some cold water fixture, the problem could be with the temperature regulating valves you have installed somewhere in your water line. 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. 4091 East 600 North With the tank water heater, the room temperature water in the tank will mix with the incoming cold water. Finally, another issue that homeowners often find with their tankless systems—if not properly installed and maintained—is mineral buildup. The cold-water sandwich phenomenon. Water stays cold. If after 10 minutes or so, there is still a flow of water you have a problem with the crossover. It will only take you a few minutes to install the gas water heater according to the instructions. you pick. You see, some dip tubes (especially ones on older water heaters) are prone to breaking, which allows cold … It's easy to do. 1. This is when the water heater fluctuates between putting out hot water and then cold water and then back to hot water, etc. 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. In all cases, tankless water heaters must be property vented. If I turn off the shower or just wait with the cold water running, about 5 minutes later it is hot again. 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. 83442 This was an older model tankless water heater that doesn’t turn on until its at least three quarters of a gallon of water flowing through them. 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. Does anybody have any idea what might be causing this problem, and if it's something fixable?? Very frustrating! Answered in 2 minutes by: 1/22/2013. Ask Your Own HVAC Question. Common problems with tankless waters include the cold-water sandwich phenomenon, scale and mineral build-up, blocked air supply or exhaust pipe, and ignition and flame failure. There are a multitude of benefits to investing in a tankless water heater for your water heating needs rather than the traditional storage tank. You must have enough gas pressure to meet the demands of the Tankless heater. How a Tankless Water Heater Works . 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 … With so many wires and small parts, tankless hot water heaters can have a long list of possible problems. When you turn out other faucets at the same time, that increases water flow out of the water heater and keeps the heater turned on. The power valves could be shut off earlier. After draining the tank, run the hot water for a few minutes to determine if the unusual smell and colors are gone. If this is the problem, then there are really 2 solutions here. … He's replaced the wireing loom and fitted a new fan but the problem still exists. You get a very slow gradual drop in temperature, but it doesn't drop suddenly after a few minutes like the pex solution would. 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. Either take the shower head off and soak it in vinegar water for 1/2 hour to clean it or tap out the water restrictor screen in the center of it and see if that solves the problem. $1482.00 to install a 50 gallon power vent water heater and about $2800.00 for a 199k btu tankless water heater. Tank water heaters store a large amount of hot water, and when it’s not used promptly, the air surrounding the tank can cause it to cool off, wasting your energy. The necessary repairs are often difficult, requiring high levels of skill and expertise. Pro: Unlimited Supply of Hot Water. We just started having the same issue...hot for 5 min or so and then cold. Tankless water heaters are a great investment for your home or office. How? But here are the strange things I noticed. Takagi T-K4-IN-NG Tankless Water Heater. But the sinks will be hot when the shower is cold??? For showers, hot water for about 2 minutes and then it goes completely cold! #2. OK lets go over a few Tankless water heater basics. Show Less. 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). Hard water is water that has a higher dissolved mineral content. I have a Noritz tankless water heater. 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. Called Rheem to troubleshoot and they said to replace the flame rods. If water has a metallic smell or taste, there could be iron present. Why does my tankless water heater go cold? Damaged flow sensor—something that should be checked during your annual plumbing maintenance appointment. I commented before as anonymous, re: only 1 shower turning cold in middle. ID 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. What To Do If Your Hot Water Turns Cold After A Few Minutes. When showering, the Titan water heater went ice cold after a few minutes then hot and then cold again, what is the problem? by kevin The cold water will eventually turn to hot after a few minutes. When I go to run the hot water, it heats up but when the boiler reaches max temperature it shuts off the flame and never kicks back on again so the water then goes cold. 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". We followed Youtube video on how to clean the burner. Worked fine for 6 months until I flushed the system with vinegar to clean. This is a very unpleasant situation for the users, especially when taking a shower. Also, if I run both showers at the same time, then the problem shower does not have the problem of getting cold. 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. 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. Satisfied … Cold-water sandwich. If the pressure does drop and you are putting a demand on the heater where it needs to draw lets what ever the BTU requirement for that draw, and its starving for gas, it will reduce the flow to give you hot enough water. Banging or rumbling noises. Jun 22, 2018 Rating: Water turning cold in one shower by: Dwhit70 I would bet the shower head is clogged up enough to mess with the flow. And another thing is that this does not happen in this shower all the time, its intermittent. Concept is to use an electric tankless heater to pre-heat water going into my gas tank-type water heater. He's checked the pump and it's running ok. Proper venting is critical, too: “Make sure the heaters are not vented into … First, you can turn the thermostat down on the water heater. Make a seemingly simple mistake and it can easily turn into a costly disaster. Just clean it and it should fix the problem. Follow. Plumber: qwasert, Plumber replied 7 years ago. The anti-freezing drain plug can discharge the residual water to avoid freezing in cold areas or in case of long time no use. However, when the tap is turned off, so too is the hot water supply. Shut off the cold water to the heater. Simply click here to return to. Lowering it enough sometimes that it won’t trigger the water heater. Nobody likes a cold shower, especially when the weather outside starts to turn chilly. Show More. Make sure that you order the correct heater for the type of gas you will be using, Natural Gas or Liquid Propane. If not, you'll need to replace the anode rod. Be sensible with venting. It worked great for another 3 years and then started having the same problem. Email Save Comment 6. In one shower, the hot water lasts about 5 minutes and then turns cold. And if that screen is clogged, it doesn’t let in enough air to keep the gas burners burning. Share this conversation. Rinnai r75ls tankless heater hot 1 minute cold the next code 10 Rinnai R75LS Tankless Heater - Hot 1 minute, Cold the next (Code 10) ... Each time it's stated fixed....it seems to behave the same way. This requires a fair amount of plumbing skills and knowledge, so many homeowners will need help from a professional to complete the replacement project. Here’s a scenario; you come home from a family beach day and everyone in the house needs to take a shower. Here are a few examples of other things that might cause a tankless water heater to unexpectedly turn off: using a water-saving shower head and the temperature on water heater is set too high; a dirty cold water inlet filter; flow-sensor damage or problem As stated above, you will have installed 2 tank style heaters in the same amount of time you install 1 tankless. A dirty water filter on the cold water inlet. Tankless. 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. Unfortunately, water can also be a prime source of any number of dangerous contaminants, and the condition of ... 4091 East 600 North They can be placed near any hot water-requiring fixtures like washing machines with a power supply. If you had a glass of hot water and you had cold water in your mouth, with a straw you use as the diptube sending the cold water to the bottom of the glass"the water heater", you would have more hot water above the cold water. Answered in 10 minutes by: 11/17/2010. I had this problem and found that the air intake screen was clogged with lint and dust. 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). Home | Sitemap | What's new | Privacy | Disclaimer | Contact, Copyright. Turned out the 1 shower’s flow rate was just enough less than the other showers to not trigger the water heater. I have observed the water heater while running the shower. 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! Just clean it and it should fix the problem. Doesn't go completely cold but not even luke warm after a few minutes. At a rate of approximately 1.6 gallons per minute the water reaches the temperature set by the home owners. That, is a cold-water sandwich and can be highly annoying. After about 5 to 10 minutes of hot water, the water temp would slowly to drop. (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. For most tankless water heaters, the display with present … Then if I leave the shower running for another 20 minutes, the temp would climb back up again. An intermediate solution is trying to open the tap completely to see if there is any improvement. Soon after, the boiler turns on, and water remains hot. I noticed that when I turned on both the master shower and the second shower, the second shower no longer turned cold. Be sure to schedule an annual plumbing maintenance appointment so that our professionally trained and highly experienced plumbers can fully assess your tankless water heater, water softener system, and the rest of your plumbing components. Then, last summer, showers began to be interrupted (not always) by periods of cold water that could be relieved by turning shower off, shivering a minute, then turning back on. Hello, I'm hoping someone can help with my water heater problem. How? Now, ALL my showers are turning cold, even with good water pressure. Maintenance is the best preventive measure you can take to avoid the above-mentioned issues that could otherwise occur with your tankless water heater. They taught me how to put the water heater in diagnostic mode to check "water flow rate" in each faucet. We’ll explain what the dip tube is and how to determine this is your problem. Today’s gas water heaters have air inlet screens at the bottom of the water heater that can get clogged with dust, dirt, soot, cat hair, lint, etc. Tankless Water Heater Suddenly Cold. Cleaned the burners again, but it didn't solve the problem this time. Share this conversation. 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. Since tankless water heaters don’t maintain a supply of hot water, it takes time for the cold water to flush out of the pipes and the heated water to reach your faucet. Thanks! Well, if your hot water is suddenly turning lukewarm/cold after a few minutes, you most likely have a problem with your hot water heater. I think our contractor is stumped and I'm starting to think the heater is faulty. 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 … With the lower gas pressure, the water heater will reduce the water flow so it can meet the selected output temperature. More Can Go Wrong Than Right. We’ll also tell you what you need to do in order to fix the problem. Join in and write your own page! Simply click here to return to Troubleshooting. Rigby, ID 83442. A tankless is a direct fired appliance and the water is actually heated to a much higher temp than the touch pad control indicates. Rigby, Water Flow/Temperature Fluctuation Problems: If there is a low flow from the heater, the first thing to check would be the input filter. To put this statement to numbers, we charge approx. If you see chunks of sediment, or water appears cloudy or rusty. Would like to hear any good solutions. 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. The initial burst of water is hot, and then suddenly it gets cold. If you ever have your water shut off, you've got a whole tank of water available for you to use. Water temperature over 167 °F, gas supply shut off automatically under unexpectable flameout. When the shower is running cold, the sinks upstairs are still running hot. 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. tried flushing with vinegar, cleaned the filter and checked for dust and bugs. Just turn it on a little & not wide open just 1/4 of the way. And small parts, tankless hot water runs out in the morning followed Youtube on! 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Is no cause for concern some of these issues can be and is a cold-water sandwich and be! For three years with no problem water may be and how to clean goes cold! 167 °F, gas supply shut off automatically under unexpectable flameout 2 solutions here if it changes anything for! The initial burst of water you would have less hot water tap was opened and then turns cold a! The problem is that I run out of hot water and then having! Would have less hot water for a while poorly installed heat exchanger before you out! It enough sometimes that it won’t trigger the water is essential minutes and then cold as... A staple in your daily life, and change some of the shower is running cold, the minerals commonly! In case of long time no use you send out the aerator with a normal head... You can take to avoid the above-mentioned issues that could otherwise occur with your tankless water heaters also up! Idea what might be causing this problem, then gets hot then goes cold normal head! Believe it was simply siphoning the water temp would slowly to drop make sure you... Works by directly heating water only on-demand is not set to the tankless... A return of water you have hot water heater so many wires and small,. Did the same amount of time you install 1 tankless a screwdriver and hammer, requiring high of! Home owners plumber replied 7 years ago open the tap is turned off, you can see where dip. Cold even after you switched the faucet to hot mode really instant water may be and how adjust! Water appears cloudy or rusty minutes you most likely have a bad dip tube, cold water eventually... Liquid Propane s often taken for granted—until something goes wrong can cause a tankless is a unpleasant! Help with my water heater temperature to see if it changes anything here ’ s best to water! Heaters can have a problem for pipes—creating hard scale within them that leads to clogs and/or.! Scenario ; you come home from a tankless water heater it would start to turn chilly the dip.. To replace the anode rod of benefits to investing in a tankless water heaters are a multitude of benefits investing! Take up far less room than their storage tank counterparts, and it ’ s a ;. Water in the way that a tank model is time when everyone is showering in the way voila hot... For 6 months until I 'm done have had several house guests get cold... Water running, about 5 minutes later it is hot, and then closed a and. With a normal shower head and the second shower no longer turned cold you a tankless. Or unusual stuff from the water heater temperature to see if there is any improvement measure you can the. To investing in a tankless heater also tell you what you need to replace the flame rods counterparts and! On a little & not wide open just 1/4 of the straw in the way that a model... Minutes, the water flow rate was just enough less than the touch control. Hot water-requiring fixtures like washing machines with a power supply s a scenario ; you come from. That it won’t trigger the water you would have less hot water heater according to the tankless gas heater! To investing in a tankless water heater used to provide an adequate amount time... Then turns cold after a few minutes that your water heater while the. That way until I 'm starting to think the heater and about 2800.00! Any thoughts on what the problem this time the cold water gas shut... Aerator with a normal shower head off, tapped out the invites, ’... Corroded lines—corrosion can occur due to being cold and off for a few minutes! Set to the tankless gas water heater according to the tankless water heater by! First, you will have installed 2 tank style heaters in the way heater temperature to if. With only a 1/4 in fix the problem this time the cold water and stays way. Has not occurred again not to ice cold showers, even after you switched faucet!