Tankless water heaters have higher efficiency than their standard counterparts that use energy continuously to keep their water tanks hot. The sweet spot with these models is that they rarely develop problems. However, they are also susceptible to technical hitches. In this article, we discuss these hitches and also guide you on how to fix some of the problems all by yourself. We also tell you when you need to get a professional on board. Shall we?
Common problems that affect tankless water heaters
There are few signals to check to know if your tank is okay. While some of these signs are easy to notice, some of them can be hard to identify.
- No hot water
- Irregular water temperatures (either not hot at all or not hot enough)
- A burner that won’t ignite
- A noisy burner
- Water pressure is low
As you may have realized, there’s one major culprit that we didn’t highlight here and for a reason; the issue of not getting hot water instantly. This isn’t a problem per se. Don’t expect some hot water right away unless your tankless water heater is fitted with a recirculation pump or a buffer tank. Why? This is because the hot water is delivered straight from the heater. As such, you may have to wait for a few seconds depending on the distance between the fixture and the heater.
How do you fix common tankless water heater problems?
Some of these problems are minor and easy to deal with. However, when damages are way beyond your expertise, that’s when you need to contact a professional plumber.
No Hot Water
This is the most common. It may be as a result of;
- A faulty source of power; either electricity or gas.
- If there is no enough water supply
To fix this
- For an electric tankless water heater, check if the power is on. Maybe the power connection is off.
- For the gas units, check whether the burner is lit. If not, check whether the shut-off valves are open. If not, the problem may be in a flame rod that doesn’t generate sparks.
- Again, check whether there’s an error code displayed on the main unit’s control panel. There may be another problem. So, if there’s one, have it rectified and reset the system.
- Lastly, ensure that your system is fed with the minimum flow rate. You may have to enquire from the manufacturer’s literature here. To make sure that this flow rate is achieved, open the taps enough. Again, ensure that the piping system isn’t clogged or frozen.
Water is hotter than usual
Another problem with tankless water heater is when the water is getting too hot. However, carefully assess the water to note if there is any abnormality.
Extremely hot water may cause scalds. Check if;
- If the temperatures settings are okay
- A broken thermostat
- Obstructions in the pipe system causing low water levels
To fix this
- First, check whether the temperatures are set correctly. If so, then set to your comfortable levels.
- The second option may be to ensure that the minimum flow, This may be due to clogged pipes or showerheads. If you are heating only small amount of water, the temperatures may be above normal. So, ensure that the right amount of water is going through.
- Lastly, check the thermostat (temperature sensor).
Water is not hot enough
- The most obvious reason for this may be low-temperature settings. Simply, ensure that the readings are between 125-130 F.
- For gas tankless water heaters, this problem may also be caused by low gas pressure. Ensure that the valve is fully open. On this point too, check to see whether the gas supply system is fitted with the correct line sizing. You may have to rely on an expert’s knowledge here. If the gas supply is sufficient, ensure that the venting system is free of debris and that there’s enough aeration for flawless combustion.
- Again, ensure that there is no clogging of the water filter and fixture aerator. Have you flushed your heat exchanger lately? Tankless units have small apertures that get clogged easily. They may need to be flushed on a 6-month basis. The deposits prevent direct contact between the water and the heat exchanger, which slows the heating process. To flush out the clog deposits, you may either call a plumber or do it yourself using either a submersible or sump pump. You’ll also require 2 hosepipes, a bucket, and 2 gallons of vinegar (white).
A burner that won’t ignite
If the burner is not working, check to see if there is any problem with the following;
- A poor vent system
- The burner has debris
- A faulty flame rod
- Wrong type of gas
- Low gas pressure level
To fix this
- Ensure that the gas pressure level is appropriate by turning the valve ON.
- Check that only the correct gas as per the manufacturer’s instructions.
- Check to see that the flame rod is operational and in the correct position. If not, reposition or replace it.
- Check to see that the burner is working well.
Low water pressure
- The cause of low water pressure may be low gas levels. This happens when the heater lowers the flow of water to heat the water to selected temperatures. As such, ensure there are optimum gas pressure levels.
- Confirm that there’s adequate water pressure getting into the heater
- Check to see that they’re no obstructions in the major components; pipes, fixtures, and filter
When should you get a professional?
As you’ve just seen, most problems arise mainly from the heating system or the flow of water. Some correctional tasks like setting your preferred water temperatures, opening the water taps and gas valves, and flushing doesn’t require professional knowledge. You can easily save your bucks here if you’re a DIY enthusiast. However, some problems call for a professional plumber or electrician to fix.
If you have enough reasons to prove that the heater is faulty, you may have to contact an electrician to check the thermostat. Again, you may also need a plumber to troubleshoot a problem with the water levels. Moreover, you need the services of the 2 patrons if you’re planning to replace the entire system for a new one or to another location.
When should you have maintenance?
- To maintain a high level of efficiency, you will need regular maintenance to keep your heating system on its toes. The average service life of a tank heating system is 10 years while that of a tankless heating system is 20 years. Regular servicing of your heater will increase the service life of your system. It will also help prevent issues that could arise in the future.
- If you regularly use hard water, it is important that you install a water softener to reduce the amount of scale build-up in your heating system
- Lastly, you might also need to flush it every 6 months to 2 years. This will prove to be helpful every time the water flow slows.
One simple way of ensuring that your tankless water heater system is at its best is by maintaining above-minimum water levels. Again, always follow the manufacturer’s recommended service schedule to detect and deal with minor problems beforehand.
While it is possible to do repairs and inspect your tankless water heater, it is best done by a professional. If you are a DIY enthusiast, you can do the inspection. Use the manufacturer guide and if you need more information, there is plenty on the Internet. Finally, always remember to do a regular checkup even when everything looks okay.