The Common Issues Around Tankless Water Heaters And How To Solve Them | San Antonio, TX

The Common Issues Around Tankless Water Heaters And How To Solve Them | San Antonio, TX

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Tankless water heaters provide you with hot water whenever you need them. Unlike other water heaters which often run even when you do not need hot water and add to your electricity bill, tankless heaters heat the water only on-demand.

However, like other mechanical equipment, these water heaters may have some issues from time to time. And when they occur, you should always give a call to your plumbers rather than trying any DIY methods of your own.

Here are some common issues which might arise in tankless water heaters.

1. Mineral Build-up

Mineral Build-Up in such heaters is common and in San Antonio, TX, where the water is usually hard, you might experience occasional build-ups of calcium and magnesium. If the scaly layer is allowed to get thick, it can hinder the smooth functioning of the heater. It will slow down the heater and might cause it to crash just when you need hot water the most.


Experts on tankless water heaters will tell you about the kind of water softener best suited for your heater. The water softener will help maintain the pH balance of the water, reducing the intensity of mineral build-up. They will flush the heater twice a year and offer regular maintenance when needed.

2. System Overload

Tankless water heaters are best used at intervals. If the heater is used beyond its capacity for multiple batches of hot water back to back, then it will result in a system overload. It might disrupt the wiring and shut down the heater entirely.


If you need more hot water, you could install a new unit with a greater capacity without putting extra load on the existing unit.

You could also add a second tankless water heaters. It might seem like a hefty investment initially, but it will save you a lot in the long run- money that you would have had to spend on repairing the heater every time there is an overload. These technical repairs can be costly. You will also use less gas to heat the water. Local experts will help you with the installation of a larger or second unit.

3. Cold Water Sandwich

This phenomenon is quite common in most homes where hot water is used very frequently. So at first, you do get access to hot water, but a little later, when someone else needs hot water, they get a little of it and then blasts of cold water start alternating before the water again heats up enough for a seamless flow.


Tankless water heaters take some time to heat up so once the hot water is completely depleted and the trapped hot water in the pipes has also been released, it might take some time for the fresh batch of water to heat up. So it is best to wait for a little before trying to draw hot water after someone has just finished.

4. Problem with Air Venting

Your tankless water heater can display an error message when the exhaust is blocked. It means that there are issues with combustion air. Check if the vent pipes are properly fitted, but call an expert for a closer look.


Experts on tankless water heaters will check if the heater meets all the clearance requirements because objects placed too close to the heater can block the vents. In case there are any obstructions like a bird or rodent nest, or some other blockage, they will clear out keeping the safety of the residents in mind. They will check there are no punctures in the vent pipes.

5. Ignition Failure

Your tankless water heater can fail to ignite if the gas supply is inadequate. These heaters mostly use propane and you can make sure that there is adequate gas for the heater to operate. If you are not sure about the gas limits, then call an expert.


The heater’s ignition could fail, and it is a technical issue best left for the experts in tankless water heaters to resolve. Replacing some parts could also be necessary. In case you have a flame failure, the expert will check for electrical issues. At times, the gas line can be too small or the regulator might not be operating very well.

6. Frozen Heaters

Just like overheated heaters can be a problem, so can a frozen heater. This mostly happens in very cold winters and San Antonio, TX has experienced some pretty harsh winters in the past. If the temperatures dip around the freezing point, the motor just might refuse to start up, leaving you devoid of hot water when you need it the most. You can also suffer from frozen pipes and some of them often burst with trapped ice.


It is best to contact experts in such a scenario, who will help with the installation of a recirculation system. They will also help with insulating the system so that low temperatures affect your heater as little as possible. You have to ensure that the power system is uninterrupted and clear the area of any standing water or ice which might hinder the system.

Get in Touch For Any Issues Regarding Tankless Water Heaters

Tankless heaters are cost-effective and usually do not require a lot of maintenance. However, you should always contact experts rather than trying methods yourself which you are not sure about.

Our experts at bluefrog Plumbing + Drain of San Antonio will take care of any issues which you might have with your heaters. We have the technical know-how to fix any problems so that you can be completely relaxed about your hot water supply.

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