How to Select the Right Size Tankless Water Heater

June 14, 2016 Home Improvement

Introduction
Tankless water heaters are way much efficient and reliable than the conventional water heaters. If you are looking forward to install a new unit or replacing your old water heater. Then you should have to determine a right size for the tankless water heater you require. Choosing a right sized tankless water heater depends upon your hot water requirement.

 

 

There are also some other factors you must take in consideration while making a decision. These factors vary for the whole house installation and with each particular application. Initial cost for the tankless water heating units is undoubtedly highbut, avoid installing an undersized water heater to save money.

 

The basic factor, which needs to be carefully looked upon when reading best tankless hot water heater is the quantity of hot water required. The hot water requirement varies separately for residential installation and commercial installation and may further vary by the number of points where the hot water is required.

 

Residential Applications
Tankless water heaters are widely popular for mostly residential applications. There are two options for opting the installationof tankless water heater depending on the requirement.
?Whole House Installation
?Point of Use Installation

 

Whole House Installation
Whole house installation refers to installation of tankless water heater that provides the hot water supply to the complete house. Electric tankless water heater’s functionality depend intrinsically on the ability of the electrical system of the house. The electric power an electric system can provide is limited, which may be not sufficient for the electric water heater in order to supply hot water for whole of the house. So, gas tankless water heaters may be a better option for whole house installation. In fact, a study has shown that whole house installation is popular than the point of use installation.
The major drawback of whole house installation is that the hot water has to travel to the fixtures too. This means that there will not be as instantaneous hot water as the hot water will take time to reach all of the fixtures. Also, if you don’t have insulated pipes then there will be a drop in water temperature by the time it arrives at the fixture. Moreover, there will be heat loss from any unused water present in the pipes between the fixture and the water heater.Hence, that also requires proper venting system.

 

Point of Use Installation
Point of use installation refers to the installation of water heater for a particular fixture or appliance like the washing machine or dishwasher. As they are installed near the fixture, they provide instant hot water on demand, so they are often called as demand or instantaneous water heaters. In this case, tankless water heater doesn’t demand large supply of electric power. They are compact in size and can be easily installed in small places. Also, they don’t require any exhaust vent. So, electric tankless water heater is a better choice for the point of use installation.
The proximity of the water heater to the fixture reduces the risk of heat loss. But there must be a proper water flow, choose the one which has maximum GPM (Gallons per Minute) flow rate. You can install different units in different parts of your house as long as your home’s electric system is able to support their operation.

 

Commercial Application
Tankless water heaters can be used for commercial purpose also. For commercial purposes, they are characterized in two categories.
?High water demand
?Low water demand

 

High Water Demand
Hotels and hospitals, for example, requires large quantities of hot water. There are some water heaters which are able to provide large amount of hot water, they have specific heating elements which can provide as much as 70-80 GPM. They are also feasible for the large industrial processes.Over a long period of usage, they prove efficient and beneficial for large scale fixtures.

 

Low Water Demand
Tankless water heaters are suitable for point of use installation in commercial processes as well. These can be used in places like diner or small offices where hot water demand is occasional. Usage of tankless water heater over standard water heaters endow financial benefits. In most of the cases electric units are used.

 

There are other factors like climate change, flow rate or power supply which are also to be consider when choosing a right sized tankless water heater.
•Flow rate – Flow rate describes how much water you need.

The table described above shows fixtures and their average flow rate. For example, if there are two showers running simultaneously, you will require 4-5 gallons per minute. The requirement of water flow increases with the increase in fixtures using it. Select the water heater which is able to provide the flow rate you required.

 

• Power or gas supply – Power supply and gas supply depends upon the requirement of the hot water. If you have a whole house installation of tankless water heater it will need large amount of power or gas supply. Size the unit which will be able to work on the same requirement of power or gas supply you want.

 

• Climate conditions – The hot water temperature depends upon the temperature of the incoming water. If you are living in cold climatic conditions, your heater is going to use more electric energy to heat water, whereas if you are in a warm place it will require less electrical energy than required for heating the same amount of water in cooler climate conditions.

 

Once you have noted all these factors, follow these steps to select a right size tankless heater for your hot water requirement:
• Decide how many fixtures you want to run and calculate their total flow rate. This will give you an estimate of the total flow rate you will require. For example, if you want to run two showers, a washing machine and a dishwasher; you will require a flow rate of about 8-9 gallons per minute.
• Determine the temperature raise you require. The required temperature rise will be different for different places. The required temperature rise is difference of the desired output water temperature to the incoming water temperature. You will require water temperature of around 105-115 degree. For example, if the incoming water temperature is 40 degrees then you will require a temperature rise of 60-70 degree.
• Check whether the power supply or the gas supply is enough to fulfil your requirements. Also check for the type of venting system and components most suitable for you.
• Last step is to order the tankless water heater which you have decided. Please make sure to check the energy star rating.

 

Conclusion
This completes this guide meant to make you aware about selecting the best-fit product for you. You can go either for the electric tankless water heater or purchase a gas tankless water heater to fulfil all your hot water requirements.
Be sure to note down all the requirements before making a purchase. You can also find the info about various sizes, builds, features, and other various specs of tankless water heaters on the web.
You can also check the latest and trending products offered in the market via the web. As a last piece of advice, always double-check your requirements against the specifications of the product you intend to purchase to ensure a long healthy relationship with the product.

 

And if you have any questions about bathrooms, you can find answers at: walkinshowers.org.