Tankless Water Heater ruining appliances and clogging pipes!

[Nes3p]

Hello. We installed an electric tankless water heater a couple of years back. Ever since, we have had to occasionally take the hose off the back of the washing machine (stops getting hot water to it) and clean it out as it has become clogged with sediment/scales or whatever it is . Our shower heads do this and have to be cleaned from time to time. My master bathtub can get a decent amount of cold water to it but the hot water is literally a tiny trickle and we cannot fill the bathtub up at all. Recently, my dishwasher kept having issues and I realized it was not getting any hot water to it. It appears that the dishwasher is now completely ruined. Over the time we have had the tankless water heater, we have installed some sort of filter outside where the water comes into the house. We also came up with a makeshift small indoor "filter" that attached to the hot water hose/s that ran from the tankless water heater. It contained a little trap and screen that was supposed to catch scale and debris. This eventually had to be removed due to issues and it popping off from the hot water pressure running through it and it caused a water leak in the laundry room. What are my options? What do I need to do exactly? I'm new to all of this and I'm trying to understand. I need my appliances and bathtubs to work! Do I need a water softener system? If so, there are systems that don't add chemicals to the water, correct? Do I need a specific outdoor or indoor filter? Also, do I need to flush the tankless water heater and pipes due to build up?

Thanks for any input and guidance!

 

[WorthFlorida]

Is it well water or city water? First get your water tested. Something in the water is reacting to being heated or its reacting to some metal inside the tankless. Ask a water testing lab if they can analyze the scale deposits.

This company manufactures a water conditioner here in Florida. It's not a water softener but at one time they were or the dealers were advertizing "water softener". On reviews many did not like these water conditioners because they were expecting soft water like a traditional salt softener and it still left hard water deposits, however, the minerals were easily washed away. It's now named "NaturSoft® Water Softener Alternatives". I just noticed on their web site they are now part of Pentair.

https://www.pelicanwater.com/water-softeners/water-softener-systems/
Perfect for some local counties that ban the use of salt water softeners in the states of Texas, California and Massachusetts

 

[Sponsor]

 

[Dana]

Hello. We installed an electric tankless water heater a couple of years back. Ever since, we have had to occasionally take the hose off the back of the washing machine (stops getting hot water to it) and clean it out as it has become clogged with sediment/scales or whatever it is . Our shower heads do this and have to be cleaned from time to time. My master bathtub can get a decent amount of cold water to it but the hot water is literally a tiny trickle and we cannot fill the bathtub up at all. Recently, my dishwasher kept having issues and I realized it was not getting any hot water to it. It appears that the dishwasher is now completely ruined. Over the time we have had the tankless water heater, we have installed some sort of filter outside where the water comes into the house. We also came up with a makeshift small indoor "filter" that attached to the hot water hose/s that ran from the tankless water heater. It contained a little trap and screen that was supposed to catch scale and debris. This eventually had to be removed due to issues and it popping off from the hot water pressure running through it and it caused a water leak in the laundry room. What are my options? What do I need to do exactly? I'm new to all of this and I'm trying to understand. I need my appliances and bathtubs to work! Do I need a water softener system? If so, there are systems that don't add chemicals to the water, correct? Do I need a specific outdoor or indoor filter? Also, do I need to flush the tankless water heater and pipes due to build up?

Thanks for any input and guidance!

There are no reasonable filters that will trap scale produced by the tankless water heater. But you correctly guessed that a water softener can dramatically reduce (though not entirely eliminate) the amount of scale formation, and consequently reduce the amount of scale thrown off.

Scale forms in tank type water heaters too, but particles of scale released off the heat exchanger tend to collect in the bottom of the tank, not the top where the hot water is drawn from, and only rarely cause issues with faucet aerators or appliances.

In any Texas location the best of both worlds (for a price in both equipment cost and potentially floor area) can be had with a heat pump water heater, which will use less than 1/3 the amount of electricity that the tankless does. If the heat pump water heater is located inside the house (rather than an unconditioned garage or attic) it will even help dehumidify & cool the house, taking a small amount off the cooling energy use. With some/many heat pump water heaters it's possible to duct conditioned space air into & from the water heater, putting the cool dry air output into the house even when the water heater is located in a garage or attic. They're not cheap, but the installation is only slightly more complicated than a plain old tank water heater. The condensate from the air side of the heat exchanger needs some disposal (the same condensate pumps used with central AC works just fine, if it can't be routed outdoors or into a drain), and if ducting the air side to conditioned space for the AC benefit or to hide it away into a closet too small to deliver enough heat there is the additional cost of the ducting. The backup heater elements of "hybrid" heat pump water heaters takes no more power than a standard tank water heater, and substantially less than a tankless electric.

 

[Bannerman]

With hard water, the minerals that cause hardness (calcium and magnesium) will precipitate out from the water and will collect on plumbing components with collection most rapid on the hottest components of a water heater. In electric conventional tank-type heaters, hardness scale will most rapidly collect on the electric elements, and in a gas-fired heater, on the tank bottom above the flame, and on the flue tube that runs up through the centre of the tank.

Tankless units deliver more heat into the water in shorter time so scale formation will usually occur more rapidly than in a conventional tank-type heater. For this reason, a tankless heater will typically require de-scaling on an annual basis, but depending on the hardness of the water, de-scaling may be required more frequently.

De-scaling is usually performed by recirculating an acid solution through the WH heat exchanger. Plain white vinegar is often used. Tankless heaters are usually equipped with inlet and outlet valves which incorporate capped connection ports that allow a circulation pump to be temporarily connected using hoses. Here is an example: https://www.homedepot.com/p/Rheem-B...r-Tankless-Water-Heaters-RTG20220AB/202798884

Flushing kits are available which include a bucket, pump and hoses for DIY flushing. Here is an example:
https://www.homedepot.com/p/RectorSeal-Calci-Free-Tankless-Water-Heater-Flush-Kit-68711/206051172

True water softeners utilize salt to regenerate the softener's capacity to remove hardness minerals. Soft water has additional benefits beyond reducing scale formation in a WH so you may want to consider those benefits before proceeding.

Salt-less methods are considered to be water conditioners as they usually do not remove the minerals that cause scaling but utilize a magnetic field to alter the alignment of the hardness minerals so they will be more likely to remain in suspension and less likely to adhere to plumbing components.

 

[Jadnashua]

To get any useful volume with an electric tankless system will require a HUGE input of power, or, as you're seeing, a very limited volume. IOW, except maybe for hand washing, an electric tankless is not a very good choice. A typical gas-fired tankless will use about a 200K BTU burner...that's over 200A, and you almost certainly don't have that much going into yours.