User-agent: Mediapartners-Google Disallow:

Nortiz Tankless Hot Water Install Part I

The begining

Drain the old tank

Disconnect water and gas

Gather parts

Nickel-stainless valves

Vent pipe and flex gas supply pipe

Wall vent stainless steel

In my neighborhood all the housing is just about the same age and I am almost the only house on the block that still has the original water heater.  This gem is over 13 years old and based upon the noise it makes and the already plumber serviced problem I knew I was living on borrowed time.

I also know, based upon being a homeowner for nearly 40 years that when any critical item fails in a home it will do so while you are away on vacation or about 2 am on Saturday morning.  It will also do it when needed most such as the coldest or hottest day of the year.

My military career has taken me all over the world and I know that the US is one of the few countries that uses a hot water holding tank to supply hot water.  Knowing that I decided to investigate a tankless system.  

There is no shortage of information on the internet to include comparisons of various systems by our government.

U.S. Dept of Energy click here and  Tankless Buying Guide, click here.

Bottom line is that there are efficiencies and cost savings to be had by installing a tankless unit versus the tank style.  I will not go into all the pros and cons but rather simply address the install.  The savings do favor gas fired units and Southern US installations.

There are 2 key issues to consider:

1)  What is the average annual  temperature rise in degree?  Since the unit has to heat the water to a predetermined temperature and provide it to the users on demand the key become temperature of incoming water and the spread in temperature to the outgoing temperature.  It is at this juncture that the tankless unit can make or break the fuel savings model.

2)  Number of users of hot water at any given time.  This will determine the size of the unit required and subsequently affect the cost savings.


There are several companies the make tankless units, Bosch, Rinnai and Noritz were the 3 finalists in my research.  I looked at a lot of factors in making my choice:

1)  Length of time in the industry

2)  Length of warranty

3)  Other features such as heat exchanger, electronics, gallons per min of hot water and the temperature rise factors.

After several months of research I selected the Noritz (click here)  brand as the unit for my home and the unit I felt offered the most for my money.  The Noritz unit has a 25% thicker heat exchanger made of copper and is rated as a commercial unit.  It comes with a 10 year warranty and a 3 year warranty on everything other than the heat exchanger.  The specific unit I chose was the Noritz 0751 Series (click here)  based upon the requirements of my household.


1)  Map out how and where you intend to install the unit.  If you have an existing gas unit then I recommend replacing in place with the new unit.

2)  Identify the water and gas requirements of the tankless unit you have chosen.  The Noritz I picked requires 3/4 in water lines and a 3/4 gas line supply.  My unit consumes 199,000 BTUs and needs a lot of gas to meet the hot water demand.

NOTE:  You may need to contact the your gas company and let them evaluate your gas requirements for your home.  You might need a larger gas meter to meet demands if you have a lot of gas appliances.  We have a gas furnace and the hot water requirement only and our unit was sufficient to meet that demand.

3)  After mapping out requirements you need to gather parts.  I found a Noritz distributor on e bay and bought it there.

TIP:  Noritz offers a vent pipe kit and valve kit.  I STRONGLY recommend you get the complete install kit with your unit.  The valves I received were of the highest quality.  Nickel-stainless steel valves made in Italy and stainless steel vent system that is so simple to put together that even a caveman can do it.  The vent system is adjustable and uses a click lock system that has silicone "O" rings for sealing.  The overall quality of the Noritz unit is truly a 10 of 10.  Every wire is labeled and it is a lesson in user interface, quality of build and innovation.

TIP:  Home Depot/Lowes and Ace Hardware will have most of the other parts you will require, 3/4 in copper etc.  But you most likely will need to order the flexible gas line as none of the aforementioned carry 3/4 in flexible gas line.  I used Brass Craft Pro Coat Flexible Stainless steel line 36x3/4 in.

Nortiz Tankless Hotwater Install page 2

Copyright 2005, '06 -  '17  All Rights Reserved.  17 Oaks Ranch Companies LLC:                                                                                 SavageSun 4x4, SavageSun Engineering, SavageSun4x4 Expeditions, SavageSunJeep, BuddysBonz