What Size Water Heater Do I Need ?

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The most common question consumers often ask when it comes to purchasing a new residential water heater is always, “What size water heater do we need, and do we have the correct size now?” Home owners want to be sure they have a water heater that will meet their daily requirements, but they do not want to spend more than necessary on a water heater that is too big for there home and may end up wasting energy and money.

It is somewhat of a balancing act to find the ideal size water heater for your circumstance. The easiest way to do this is to let a professional handle the job. You must have professional plumbing specialist to install the system, so it is best to have them with you from the beginning to select the type and size of water heater that is ideal for your home.

How to Determine the Correct Water Heater Size

Let us show you a bit of what goes into the proper sizing for a water heater. It is much like sizing a heater or air conditioner for a home, sizing a system aims for a “sweet spot” of that is large enough to meet demand, but not so large that it is wasteful. It is best for a professional to come out and go over the options and size the system properly, then to just do it yourself. You could be not getting enough hot water or wasting money with too big of a system.

Peak hour demand. This is the time during the day when you will use the most hot water. The H20 plumbing professionals will work with you to make these calculations based on how many people are in your house and what time of day the most hot water is used. For the majority of homes, the peak hot water use is in the morning when people are showering. Think of a hotel and how much hot water would be needed for everyone who woke up and took a shower at the same time. This number is used to determine the best first hour rating. So if your peak hour demand is 40 gallons for your home, the best match for a water heater would have a first-hour rating of 38 to 42 gallons.

The first hour rating. For a tank or heat pump water heater, the first hour rating is the number of gallons of hot water the heater can supply per hour if it starts with a full tank of hot water. This is the first rating professionals look at since it combines a number of other factors such as the tank capacity, the energy source, gas or electric, and how much heating power it has. BTU’s for gas and KW for electric.

Maximum temperature rise at given flow rate. If you are going to have a tank less water heater installed, the calculations are different since these water heaters do not store water but heat it up as it is needed. The professionals must determine the flow rate and the temperature rise necessary for the whole house. This requires determining the number of hot water appliances that might be in use at one time, then adding up how many gallons per minute they use. This determines the flow rate. Subtracting the incoming water temperature from the desired output temperature determines the maximum temperature rise. Once the professionals know these numbers, they can accurately size a tank less water heater for a home. This calculation is very important and should not be ignored. Everything from the proper size of water heater to the proper size of gas pipe has to be determined for the correct installation.

This all sounds complicated, but we are professionals with experience handling water heater installations. We offer excellent service for the middle Tennessee area. If you have any questions or are looking for a professional water heater installation then please give us a call at 615-864-9459 and a H20 plumbing specialist can come out and determine your needs and help you with your unique circumstance.