Reasons Your Tankless Water Heater Takes Longer to Heat Water

November 4, 2018 Posted By Matt O'Brien


These days, lots of praises are being sung of tankless water heaters, and for good reason. Compared to conventional storage water heaters, tankless water heaters are regarded as a much better investment. That’s because operating a tankless water heater costs less in the long run compared to the traditional storage water heaters.

Still, tankless water heaters are not without its disadvantages. Of its cons, perhaps the most common is about the longer time it takes to heat water than conventional water heaters. Here are some of the reasons your tankless water heater takes longer to heat water.

Tap may not be Fully Turned On

It is possible that your tankless water heater is not heating water fast enough because the tap isn’t fully turned on, which means only a trickle of water is running through it. After all, some tankless water heater designs do not ignite without a full flow. The heating element only kicks in when you turn the tap all the way up. Turn the tap on partially, and you’re likely to get the cold water treatment.

Too Many Hot Water Users at the Same Time

Unlike conventional water heaters with storage tanks, tankless water heaters do not store liters upon liters of water to keep your hot water needs properly satisfied for some time. While a tankless water heater can provide a few liters of hot water at all times, it can only deliver such at a time. So don’t be surprised to get cold water every now and then when everyone in the household is taking a shower, doing the dishes and laundry at the same time.

Water in any Downstream Supply Line is not Heated

It is a fact that the water in any “downstream” supply line is not heated even when you turn the tankless water heater on. That is probably why the initial flow of water is almost always cold before the heating kicks in and heats the rest of the flowing water.

Power Supply Problems

When you have a traditional water heater with storage and the power source of the heater—whether gas or electric—is out, you can expect to have continuous hot water, as liters of it are held in reserve. Tankless water heaters, on the other hand, obviously will not work as long as the power is out, and that means cold water only until utility services are restored.

Tankless water heaters have pros and cons, just like conventional storage water heaters. So if you’re thinking about buying a new water heater for your home, you would do well to make comparisons to make an informed decision on which type of water heater to go for.

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