Tankless water heaters have gained a lot of popularity over recent years. This isn’t a big surprise because of their enhanced energy efficiency when compared to traditional water heaters. However, just like any other appliance in your home, a tankless water heater can experience some basic issues.
Low Water Pressure
One of the most common causes of low water pressure from a tankless water heater is a buildup of debris. This debris is composed of mineral sediments, like calcium and magnesium, that are present in hard water. As this debris builds up, your system’s filter will become too full of it and restrict the flow of water throughout your water heater.
Fortunately, preventing this problem is fairly easy to do. You’ll want to clean the filter for your tankless water heater at least once every six months. If your water is very hard, you may want to cut this cleaning time down to every three months. Furthermore, having a professional regularly flush your system can help to dislodge any sediment buildup that snuck past your system’s filter.
Producing Cold Water or Shutting Off Completely
Unlike traditional water heaters that have a large storage tank of hot water you can use, tankless water heaters rely on being able to heat water as it flows through your supply line. This is fine when there is a reasonable demand for the water. However, when you run multiple appliances and fixtures at once, you can end up causing a demand too large for your water heater.
If it becomes overloaded due to this excessive demand, it can produce cold or lukewarm water at your fixtures. It simply isn’t able to spread out the hot water across all the fixtures and appliances that require it. Furthermore, as an added safety feature to prevent permanent damage from happening to the water heater, some units will even shut off when they’re overloaded.
Preventing this issue can be done by seeing that you get an appropriately sized tankless water heater. Having one of our plumbing professionals assess your home’s water needs can help to determine that you get the right size. Furthermore, if you add an addition to your home or put in a second bathroom, it’s important to consider the need to upgrade your existing tankless water heater to one that has a higher GPM rating.
Water Isn’t Hot Enough
One really frustrating issue you may encounter with your tankless water heater is that your water simply isn’t hot enough. If you’ve ruled out running too many items as the cause, the issue may lie with one of the unit’s temperature sensors. Tankless water heaters have temperature sensors that are responsible for detecting the incoming and outgoing water temperature.
If the outgoing sensor is defective or calibrated incorrectly, your unit may be producing colder water. To prevent this issue, it’s best to have a plumber service your unit annually. During this service, they will test the sensors for any defects and replace any faulty ones.
Failing to Heat Water
Another reason that your tankless water heater may be producing cold water is that it has an ignition problem. This is prominent in water heaters that are fueled by natural gas or propane. If the electric ignitor fails to send a spark to the burner, the burner won’t light.
Furthermore, if the burner, fuel supply line, or flame sensor is dirty, it can prevent the burner from working. The best ways to prevent an ignition issue are to ensure that you always have an adequate supply of fuel available and that a plumbing professional services your unit at least once a year.
No Hot Water at a Particular Fixture
One surprising issue owners of tankless water heaters run into from time to time is that they keep getting cold water from one of their fixtures. However, when they switch to using another fixture, they get hot water as they normally would. One likely cause of this issue is that the fixture isn’t demanding enough water.
Most tankless water heaters have a minimum water flow threshold that tells them when to turn on their burner or internal heating element. If the fixture that you’re using is below your water heater’s minimum flow rate, then its size could be to blame. Preventing this issue is as easy as reading the minimum water flow threshold for your tankless water heater and upgrading any fixtures that don’t meet it.
Water That Smells Foul or Tastes Bad
The quality of your water will be highly impacted by your water heater. The best water will be clear and scent-free. If you notice that your water has developed a foul-smelling odor or a nasty taste, then it’s an indication that something is amiss with your tankless water heater.
Some possible causes of the unfavorable water include bacteria buildup, mildew growth, fungus growth, and even excessive sediment buildup. Preventing this is as simple as ensuring that you regularly change your water heater’s filter and you have a plumbing professional perform regular flushing service.
Cold Water Sandwich
One dreaded issue that you may run into with your tankless water heater is a cold-water sandwich. This happens when you’re taking back-to-back showers. When you initially turn on the water, it will be warm. Then, it will drop almost immediately to a cold temperature. After a little while, it will return to its normal hot temperature.
This cold-water sandwich happens because of the difference in water temperature in various areas. The water right at your shower head will initially be hot. However, the water in the supply line from the outlet on your water heater is going to chill down quickly. This creates the cold-water effect that you feel. As the shower continues, the water heater will start heating up the water flowing through it, which creates the other hot part of the sandwich.
Unfortunately, there’s nothing you can physically do to your tankless water heater to prevent this issue. However, if it does bother you a lot, you can consider installing a hot water recirculation pump. This will take the water from all your hot water lines leading from the tankless water heater and recirculate it regularly to get reheated.
Inconsistent Water Temperature
When you turn on your hot water, it will likely run cold for a few moments until the hot water from your water heater reaches that fixture. Once it gets there, the water should remain at a consistently warm temperature. If you notice fluctuations in the water’s temperature, it could be due to a buildup of debris. Preventing this problem is done by getting annual flushing service and regularly cleaning your water heater’s filter.
Depend on Local Expertise
Liberty Comfort Systems offers helpful tankless water heater repair, maintenance, and installation service for the Anoka, MN area. We can also assist with all your heating, air conditioning, indoor air quality, duct cleaning, humidifier, dehumidifier, electrical, plumbing, new construction, commercial, and basement finishing needs. Call us today to book a service consultation with one of our skilled professionals.