#1 Home Improvement Retailer

Internet #205078015

Model #0100156

3/4 in. Lead Free Copper Tankless Water Heater Valve Installation Kit

  • Simplifies the installation and use of tankless water heaters
  • Kit designed to replace up to 18 fittings and 16 connections
  • Backed by a limited warranty for your satisfaction
  • See More Details

Frequently Bought Together


Product Overview

Series LFTWH tankless water heater valves are designed to simplify the installation, maintenance and operation of tankless water heaters. They replace up to 18 fittings and 16 connections used in typical tankless water heater installations. Available in two valve sets or as a single valve with female threaded, union or quick-connect end options.
  • 2 valves for hot/cold tankless water heater valve
  • Hot and cold valves certified to NSF/ANSI 61
  • Lead free
  • Replaces up to 18 fittings and 16 connections
  • Color coded tee handle
  • Staggered connection points for ease of installation and access
  • Integral purge and drain valve for convenient water heater draining and for simplifying water heater flushing operations
  • Valves are suitable for most tankless installations
  • No additional adapters required
  • Kit includes: LF4L: Lead free poppet type pressure relief valves for protection against excessive pressure- LFTWH: Lead Free Tankless Water Heater Valves
  • California residents

Info & Guides

You will need Adobe® Acrobat® Reader to view PDF documents. Download a free copy from the Adobe Web site.



Product Depth (in.)
Product Height (in.)
Product Width (in.)


Compatible Brand/Model
Finish Family
Bronze/Copper Metallic
For Use With
Electric Tankless,Gas Tankless
Pack Size
Product Type
Product Weight (lb.)

Warranty / Certifications

Manufacturer Warranty
Limited Warranty

Questions & Answers


where is it made

Asked by bob March 6, 2021


What is the complete Watts nomenclature code of this set to determine EXACTLY what it is and all ...

Asked by Doug July 30, 2020

Thank you for you question. Because Watts is such an old company they essentially use two distinct numbering systems. The problem is that some literature uses the old, some use the new and some uses both. Every Watts product/SKU now carries a unique and distinct number. Watts refers to that as there EDP code. Every variant created by options or size would have a different EDP code. In this case that number is 0100156, Then you have the traditional numbering system which in this case would be LFTWH-FT-HCN-RV. This number number can be decoded to let you establish basics about the product but it is not uniquely discrete. Meaning for example that same traditional number could be available in a number of different sizes. As to the other part of you question this tankless valve kit comes with a relief valve manufactured by Watts. The EDP code on that valve is 0556050. The traditional nomenclature is 3/4" LF4L-150. The "LF" indicates lead free brass and the 150 indicates the pressure rating at which it will blow off. 150 PSI is essentially standard for residential potable water heaters. It does not have a temperature probe similar to the ones found on tank type hot water heaters such as the Watts 100XL. That is because tankless water heaters have little to no stored water so they use a different style of relief. Again thank you for your thoughtful question . We will ad the specification sheet for the relief valve for the benefit of others moving forward.

Can a thermal expansion tank (2 gal size) be used on the cold water in line to a tankless water h...

Asked by Doug July 30, 2020

To begin, a system where water is heated for potable applications is not closed. It is open. When you turn on a faucet you are opening the system. Further potable water, aka drinking water, contains oxygen. Again this indicates that the system is open. Closed loop systems stay closed and use oxygen depleted water over and over again. the most common would be a hydronic heating system where you have a boiler that heats the same water over and over again and uses that water as a heat transfer liquid to heat the structure. Second thermal expansion tanks that are on water heaters and hyrdonic expansion tanks that are on boilers, are not hammer arresters. Granted in some applications they may ironically mitigate hammer but that is not there intended purpose. Water hammer is absorbed by a hammer arrestor place hear the source of the hammer. The source of the hammer is typically a quick closing valve, such as the solenoid valve used in a washing machine. The source is typically not a water heater. Although some newer style heaters do have quick closing valves so I do discount the possibility. Hammer arrestors can mitigate the system but the best solution is to fix the problem, either by reducing the pressure, properly securing the pipes or both. So if thermal and hydronic expansion tanks are not hammer arrestors, What are they? . When water is heated it expands. That is a law of physics. Boilers typically operate at 15 PSI. At 30 PSI the pressure relief will blow off. In order to prevent the pressure from rising the system needs the ability to get bigger and smaller depending on the temperature of the water This way the system pressure will remain constant. In the old days they would use something similar to the overflow in an automobile radiator. Expanded water would leave the system and then get sucked back in was it cooled. However this essentially makes the system open and can allow air in. As air will corrode the ferrous metals boiler engineers invented the expansion tank. A tank with a diaphragm across the center. On one side is the system water and on the other and inert gas. As the boiler is heated the expanded water pushes against the diaphragm making the system larger, When it cools the gas on the other side of the diaphragm pushes it back into the system. The internal system pressure remains constant and the system remains closed. Thermal expansion tanks are different from boiler expansion tanks in two major ways. First any ferrous metals used are coated so that the oxygen in the system does not cause them to rust. Second pressure on the gas side of the diaphragm is much higher because domestic water supplies are are much higher. Thermal expansion tanks essentially did not exist until the 1990's Why? because they were not needed. When water inside the heater was heated it would simply expand backwards into the street and forwards into the house. However two changes took place. Due to legionnaires disease pretty much every water meter in this country was changed. Check valves were added so that water could not move backwards once moved by the meter. Second faucet technology was up ended by the emergence of the ceramic valve cartridge and the rubber washer went the way of the dinosaur. These valves have no give . The result, the expansion of the heated water could not be absorbed by moving forward or back. Thus pressure builds. If your base line cold water pressure was abnormally high, such as mine at 105 PSI, once heated it could reach 150 PSI. When this happens the pressure relief will burp. The pressure is relieved by the removal of hot water which is instantaneously replaced by cold water. Then that is heated and it burps again. The solution was the thermal expansion tank. The air pressure on the gas side of the diaphram is matched to the cold water supply pressure; this positions the diaphragm appropriately for that home. Now when the heated cold water expands the system has a space available to accomidate it. The result? pressure remains constant. The sad part is that in most applications the gas side of the tank is never matched to the cold water supply pressure so the vast majority of thermal tanks out there are doing nothing at all; except satisfying the inspector that wants to see one in every installation because that is what the code book says. As to installing one on an instantaneous heater. As there is no stored water and the water that is heated is so minute in quantity I cannot see the logic. However I am sure there are inspectors that will insist on them. The irrational requirements and interpretations of code made by some inspectors have never ceased to amaze me. Lastly you mention a pressure regulating valve. These comes in many varieties. I assume you mean a pressure reducing valve. If so you should be able to set the out put pressure to something nominal and consistent. Then based on the BTU's of the heater and the quantity of heated hot water storage, size the thermal tank appropriately. However keep in mind. pressure reducing valves work well and for a long period of time when water is running through them and they are in operation. However it is not uncommon to have water leak through them when the faucets are closed, after about a year. Thus if the system has a gauge you will see the system pressure rise when the system is off. Then as soon as you open a faucet it drops to the set point. The you shut the water off and it slowly starts to rise. Best of luck. Chris 9786513301

Do they reduce to 1/2 inch water connection

Asked by HONDO April 16, 2020

You will need to buy a 1/2 inch to 3/4 inch bushing to do that.

Can I use 3/4 SHARK BITE PEX?

Asked by DeeseFam7 October 29, 2019

Use copper pipe. Mike

can you use this with well water??

Asked by moss October 8, 2019


Do these valves require Teflon tape?

Asked by JimB January 8, 2019

Too much tape and maybe you should have used a GOOD pipe dope on the fittings instead ? just a thought but I think 5 wraps with T Tape is too much

why is it, that NO ONE ever talks about water flow values,,, I have yet to read of any one talk a...

Asked by Orville November 14, 2018

Well Orville the reason for the water flow valve is it has a water port you can run a cleaner of sort to clean out your tankless water heater once a year, if you have hard water or more. I don't know if this was the answer you were looking for.

What fittings do I need to hook up a new system

Asked by DR November 4, 2018

Well Dr standard pipe fittings nipples, elbows and what every it takes to make it work for you. I might suggest using Pex plastic pipe(comes in three colors) and Sharkbite fittings for your hook up . The pipe is stiff but will bend some what and easy to work with, it can be cut with a tubing cutter or a hack saw The plus side the fitting can be taken off the pipe with a special tool if you have to redo the fittings hook up, to long or to short, your Home Depot pluming guy can set you right up, don't forget pipe dope or fitting tape. Make sure you add a in line filter to your hook up if you thank you need it. good luck 86

I am contemplating replacing an old storage water heater with a tankless water heater. My incomin...

Asked by David September 2, 2018

Looking into Pex plastic pipe and Sharkbite fitting sold at Home Depot lot easier then metal pipe!

3/4 in. Lead Free Copper Tankless Water Heater Valve Installation Kit - page 2

Customer Reviews

  • 4.2
    out of 122 reviews
  • 86% recommend this product
Filter by:
Showing 1-10 of 122 reviews
Perfect for the application it was intended for. Great product....
Perfect for the application it was intended for. Great product.
by A1
A little pricey, but worth it. They are quality valves that will not leak like cheaper models.
A little pricey, but worth it. They are quality valves that will not leak like cheaper models.
by ReggieGM
This was an easy install for new construction in my basement. All the parts were there and it we...
This was an easy install for new construction in my basement. All the parts were there and it went in with no leaks. The valving is convenient, purging easy... No leaks.
by Columbia222
Response from WattsWaterMay 3, 2018
Thank you for your positive rating. We really appreciate the feedback and if there is ever anything we can assist with please feel free to contact us. Watts
3 people found this helpful
We chose this particular kit specifically because the description says: "Replaces up to 18 fittin...
We chose this particular kit specifically because the description says: "Replaces up to 18 fittings and 16 connections," and one other reviewer suggested this was "everything you need", so we assumed any and all necessary adapters were included. Nope, we just as well (if not better) should have gone with the less expensive set. · If you aren't going to use the pressure relief valve, you will need to buy a plug for its intended hole. · If you have female end supply line hoses attaching to male ends on the water heater, these female end valves will indeed attach nicely to the water heater, but not so much to the supply lines; you will need to buy double male coupling nipple fittings. · Item is NOT actually lead-free; it's simply at or below the official government approved allowable amount, but that is more than zero. (The less expensive set at least implied the strictest lead-free policy.) We don't really know which 18 fittings and 16 connections they think they're replacing, but it's still not enough to complete the job. Once we bought the additional parts, the valves did install just fine and work well, though. Nonetheless, we suggest you buy the less expensive set and use the money you save towards buying the other not-included parts you'll need.
by Jayson
6 people found this helpful
Purchased the Tankless Water Heater Valve Installation Kit when I had a Rheem 9.5 gpm tankless wa...
Purchased the Tankless Water Heater Valve Installation Kit when I had a Rheem 9.5 gpm tankless water heater installed. Product came quickly, (in a few days) and was well packaged. Parts were high quality being made of heavy brass and steel. I believe they made the water heater installation easier and matched up with the recommended installation layout that came with the the water heater perfectly. I mounted my heater on well anchored boards attached to a cinder block wall. So the heater is out from the wall about 2 inches. Since the pipes come out the bottom of the heater, these couple of inches of clearance allows me to get my hands arounds the valves, which is important as the valves will need to be used for annual maintenance. How well they function in future years, time will tell.
by BillChattanooga
4 people found this helpful
Shipping and packaging were great. The valve, however, was...
Shipping and packaging were great. The valve, however, was a total fail. The hot water side leaked no matter what the installer did to stop it. The flow of the leak at its least was enough to fill a utility bucket overnight.
by PAM
Rating provided by a verified purchaser...
Rating provided by a verified purchaser
by HomeDepotCustomer
No information about o-ring on documentation. I had to...
No information about o-ring on documentation. I had to call Watts directly to get size because original got pinched and I have some leaking.
Rating provided by a verified purchaser...
Rating provided by a verified purchaser
by HomeDepotCustomer
1 person found this helpful
This is a 3/4" set of fittings. As it turns out, I purchased a 11Kw Tankless Water Heater and, ac...
This is a 3/4" set of fittings. As it turns out, I purchased a 11Kw Tankless Water Heater and, according to the information on the HD website, this was "frequently" purchased with this item. Additionally, in many jurisdictions, the PRV is required on all water heater installations. The 11Kw Tankless water heater has 1/2" fittings - which means that I needed to purchase some bushings to convert the 3/4" to 1/2" - at a significant additional cost, or return the set of fittings for a set of 1/2". Apparently, neither HD nor other Big Box Stores carry a 1/2" Installation Kit - at least I could not find one in person or on-line. The 11Kw Tankless Water Heater required a 60 amp circuit breaker (according to the information in the package - only a 50 amp was required on the HD website). Getting the electrical to the location proved to be more difficult than I had thought it would be. As a result of the difficulty of installation and the difficulty of getting the correct required PRV Installation Kit, I gave up the project and took everything back. I gave this an average rating because it appeared to be an acceptable kit, but HD's website recommended it and it was the wrong size.
by BenS
Showing 1-10 of 122 reviews