If these steps do not resolve the ignition problem, then either your ignition pack has failed or there's a bigger problem. Tankless water heaters are generally low maintenance and very efficient, but problems can still occur. Although tankless water heaters are also called "instantaneous water heaters," they still take time to heat water, so after the trapped water was used up, you were left with a gap of unheated water. When a hot water tap is turned on, cold water travels through a pipe into the unit. Is the minimum water flow rate achieved? Since a minimum flow rate is required to turn on a tankless water heater you can’t turn your hot water faucet on with a trickle or low flow of hot water because it won’t turn on the heater. You turn on the shower and feel warm water at first, but then get blasted with several seconds of cold water before the temperature slowly climbs back up. Have the gas technician check if there is a problem with gas supply or elements. Solution To Takagi Tankless Water Heaters Problems Manually Problem: Insufficient Hotness Of Water. When the second shower began, the initial warm water you felt was the trapped water. If you are the owner of a "smart" tankless water heater from Rinnai, Noritz, Paloma, Bosch, Takagi or similar, this troubleshooting guide is for you. Low-flow faucet or showerhead. Your water heater may struggle to supply the hot water needed or shut down altogether if it becomes overloaded. Besides, the filter could also be clogged by dust or unusual stuff from the water supply. This step is particularly important if hot water supply flow rate is … Depending on your tankless water heater's capacity, too many simultaneous hot water applications (such as multiple showers running) can overload your water heater. provide a means for us to earn fees by linking to Amazon.com and affiliated Keep in mind that some unusual activities are normal; such as when the fan motor is still spinning after the water heating operation stopped. Ensure that the flow sensor is working correctly. Low Water Pressure. Leak in the sealed combustion results in irregular gas combustion. Often, this issue is caused by the gas supply, so check to make sure your propane tank is full before you do anything else. Check for clogged faucet strainers, clogged shower heads, partly closed or clogged plumbing fixture hot water stop valve. The water draw is greater, and many applications are running at the same time. An inlet filter is dirty and clogged. If the water flow is reduced due to the obstructions in the water filter or plumbing, only the small amount of water will be heated resulting in higher than normal temperatures. Just like ignition failure, you should first rule out simple causes such as a low propane tank or an unpaid gas bill. Replace it if required. Rinnai tankless gas water heaters need a demand of at least 0.4 to 0.6 gallons per minute of water flow through the hot side to ignite and 0.26 gallons per minute to stay in operation. Refer to your product manual to make sure the clearance requirements are being met, as installing your water heater too close to other objects can block the air supply and create a fire hazard. In March 2016 we had to replace the ignition switch. Everything …, Vibrating noise in the pipes We had our Noritz tankless installed professionally about 4 months ago. The first things you should check are the correct supply of electricity, water, and gas to the water heater. The time it takes to deliver hot water from the heater to the fixture depends on the pipe length between these two points, unless the recirculation system is in place. It is essential to understand that tankless water heaters are not instantaneous; therefore, they do not provide hot water as soon as you open the tap. If not, check this article that deals with the. See if there is an error code on the unit's control panel, which blocks the heater from running before the previous issue has been solved and system reset. …, gas does not ignite Hello, Some may have a different size or thread type; 3/4" NPT, 1" NPT. Some problems are possible to fix only with the right tools and skills, so to keep the warranty valid and unit functional, it is at your best interest to contact a professional plumber. They are expensive, efficient, environment-friendly, have the advanced technology, could display an error code, but can also fail and cost you a lot to fix. If this happens, you should reduce the demand for hot water by limiting simultaneous applications, and you may want to consider resetting your unit. Most tankless water heaters are equipped with a diagnostic system that incorporate the microprocessor and LCD screen, which displays an error code if the problem occurs. See how to repair a tankless heater when there is no hot water, water is too hot, there is not enough hot water, the pressure is low, cold water sandwich (the temperature of water fluctuates: hot-cold-hot), the gas burner doesn’t ignite, and what to do if there is an error code. Sediment in the hot water tank has the same effect. The air supply and specialized exhausts have a tendency to get blocked, which usually makes the device shut down. 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. Poor flow sensor leads to little or no supply of hot water. This article was originally published by Robinson's Plumbing Service and edited by Eccotemp. Venting tubes that are too long or convoluted typically cause this type of problem. Not only are they highly efficient, but they can also save you money by heating water only on-demand. With so many wires and small parts, tankless hot water heaters can have a long list of possible problems. Extreme care should be used at all times to avoid contact with energized components inside the furnace. The water heater won't turn on if its energy supply is off. Other possible causes of flame failure include a gas line that’s too small, regulator failure, combustion issues, venting and more. Each manufacturer should specify the minimum flow rate for the models they supply, measured in gallons per minute. Make sure that the tap is open enough to ensure the required flow rate, and there are no obstructions in the piping line. First, inspect all vent pipes to ensure they are connected properly and free from puncture holes. Moreover, a problem may also be in the regulator. my tank less gas water heater was working fine, this one works on the water flow principle, if the water flow and pressure is sufficient, the …, When We First Turn On Hot Water We Hear This Loud Noise Outside We have an external Hot Noritz tankless water heater that was installed in May of 2008. Check and open gas and water valves fully. Ensure that the gas type and pressure are correct and the gas line is sized correctly. If I turn off the shower or just wait with the cold water running, about 5 minutes …, Water too hot or too cold I Have an electric on demand hot water heater it provides very hot water but cannot find the sweet spot in the shower. The trapped water is now gone, but the heater still didn’t heat water that fast, so you were exposed to cold water. Does the gas control valve open at all or there is a short circuit? This is not usually what happened, but if there is no water coming out, then you should go check your pipe valves and water inlet filter. An error code can appear due to many reasons, from a simple spider web and air/exhaust blockage to more serious gas or exhaust leak. For example; the water got cold during the shower because the flow from the tap was below the minimum. Check if the burner is burning the gas with the clear, light blue flame. Most tankless heaters are setup with service valves that have 3/4" hose thread so you can attach washing machine type hoses for a service pump. Ensure there are no obstructions in the plumbing, fixtures or water filter. Hard water (in contrast with soft water) is water with a high mineral content, and the harder your water, the higher the potential for damaging mineral buildup. Burning the gas technician check if the electricity, gas, and high operating.! 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