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So You Have a Tankless Water Heater… Now WHAT?

turning water heater temperature dial

How to Keep Your Tankless Water Heater at Peak Performance

Have you recently installed a tankless water heater or looking into getting one? You may now be asking yourself, what do I need to do now or what are the water heater maintenance requirements with this unit?

With today’s high energy cost and inflating utility bills several people are choosing to go with a high efficient tankless water heater, even with the higher cost of installation. Today’s tankless water heaters achieve an amazing 97% thermal efficiency which greatly outperforms the old storage water heat.

However, due to the size of the tankless and the way the water is heated it is prone to scale build up inside the heat exchanger. This is not only an issue with tankless water heaters but in any type of system that heats water. As water is heated the heavier elements like calcium separate from the water and bond to the coarse internal surfaces of the plumbing. This is why it is noticed more on the hot side of a plumbing system. Over time this will lead to the unit not producing hot water and in severe cases can lead to the heat exchanger developing leaks prematurely. Which ends up costing the owner to pay and replace the heat exchanger.

Some common signs that the heat exchanger needs to be flushed

2 tankless units - So You Have a Tankless Water Heater... Now WHAT?

  • You start noticing reduced hot water volume coming from the fixture
  • Water temperature that fluctuates while using hot water
  • Or the unit is displaying error codes related to overheating

By flushing the tankless water heater on a routine schedule, which frequency is determined by water quality, water usage, and temperature set point, typically it required once a year but running the unit at high temperatures or putting a large demand on it like a commercial kitchen can lead to the unit needing to be flushed more frequently.

When flushing a tankless unit, we mechanically remove the scale buildup from the inside of the heat exchanger (the heart of the system) by using a pump and cleaning solution that restores the units’ water passages to a like new condition. This is also the first step in determining what is wrong with a tankless unit. If the internal passages and sensors are not clean, these parts cannot be properly checked for proper function. By flushing the unit, we maintain the high efficiency of the tankless unit and the life expectancy of the unit. It is also commonly recommended by the manufactures to have the tankless unit flushed to maintain the warranty.

This process takes about an hour from the time the technician shows up to the time they leave. Typically, the inside of the tankless unit cabinet is checked for visual signs of damage at this time as well. With having a certified technician perform the routine maintenance on your tankless unit you can feel confident you will have many years of endless hot water from the unit. And enjoy the continued benefits of the highly efficient tankless water heater.

How the tankless water heater unit is typically flushed:

tankless drain - So You Have a Tankless Water Heater... Now WHAT?

  • Disconnect power from the unit
  • Shutoff water on the hot and cold side of the unit
  • Connect stainless steel hoses to service hookups
  • Connect cold side to pump
  • Place pump and hot line hose in a 5-gallon bucket
  • Fill bucket with 4 gallons distilled vinegar or tankless cleaner (mixed to manufacturer specifications)
  • Flush system for 20 to 45 minutes (depending on cleaning solution)
  • Drain tankless and discard solution
  • Clean inlet water filter and reinstall
  • Close cold inlet service port
  • Run fresh water through tankless unit to drain for 10 minutes
  • Close hot service port and turn hot water back on to home
  • Power unit back on and check for operation

As you can tell there are a lot of steps and sometimes it may be best to leave it to the professionals so if you find yourself in need of some assistance or just need a few questions answered please give us a call at (816) 920-5955 or click here and we will get you handled. You can also take advantage of our special $99 flush deal going on for February!

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We offer 24/7 Emergency Service to all of our customers. You can always count on R-Mech Experts to get to you fast and get the job done right the first time. We use state-of-the-art diagnostic equipment to find the source of your heating and air conditioning problems and fix them fast.