gas-water-heater-tank-size-pic1We often blame the poor hot water heater thermostat when we don't have enough hot water. Is it really the fault of the thermostat? How many people do you have in the have in the house? Do you have teenagers? It could be that your hot water tank is smaller than you need.

Do you have five or more people in the house? Would you consider your demand high? You should probably have a 75 gallon hot water tank. 50 gallons minimum.

I had a 60 gallon gas hot water tank when my children were at home. We got by, but often we did not have enough hot water (six people in the house). After all but one of the children moved out, I had to replace the tank. Forty gallons, no problem, right? Well, I put in a whirlpool for my wife and she still complains that there is not enough hot water.

Water Heater Recovery Rate

The size of the water heater is one thing. If no one has used the hot water for a while, you have a full tank of hot water at your disposal. What happens when the hot water starts to get used. In the morning when everyone in the house takes a shower. When you are washing clothes or running the dishwasher. Then the water heater needs to 'recover' or heat more water.

The recovery rate is as important if not more important than the size of the water heater.  If everyone gets ready for the days activity in the morning and you have an hour and a half or two hour window of time. The question would be, how many showers can the water heater handle.

Understanding Recovery Rate

When you don't have enough hot water, understanding the recovery rate of your water heater, may help to keep things in perspective. Water heaters can only heat water at a certain rate. Gas water heaters are faster than electric ones.

The things that needs to be understood is that stated recovery rates are calculated on 'temperature differential'. Boy that's a mouthful, what does that mean. Well it sounds more complicated than it really is. Let's say you live in the Northern part of the United States, the water is going to be colder coming out of the pipes than if you lived in the Southern part of the country. So the stated recovery rate may vary somewhat.

Continuous Use

It may seem like simple math. You have a fifty gallon gas hot water heater with a 40 gallon per hour recovery rate. You have a combination of five adults and teenagers that need to take showers. At an average of 8 gallons of hot water per shower you should be good, right?

The reality is that if all five showers are taken in the space of an hour, the last two or three may not have the desired level of hot water. After the first shower, eight gallons of cold water have been introduced into the tank. The water heater starts working, but now the second shower has started and more cold water is brought in and so on and so on. Depending on the length of the showers and other factors, you may come to the conclusion that getting up early is the best way to insure a hot shower.

Electric Water Heaters

If you have an electric water heater and have significant hot water demands you could be looking at a tank that is 80 or 120 gallons in size. This is mostly due to the slower recovery rate for electric water heater.

Gas Water Heaters

Water Heater Sizes

The size of you water heater is important. The traditionaal concept of 'more is better' is somewhat true. Obviously, a bigger water heater will have more hot water. However, hot water needs play into the equation. For a small household, say one or two people, why would you want to keep sixty gallons of hot water when you probably could do with thirty? Remember, you have to pay to keep that water hot. If you heat it and don't use it, you are wasting money.

So the question is, what is the proper water heater size for your house?



Bottom line, hot water tanks need to be sized by needs. Making the water so hot that it will scald you if someone turns a faucet on is not a good solution. You may need to think about a larger hot water tank.

Replacing your hot water tank is a big job. Not impossible, juts some work. Do you think you are up for the challenge? Take a look at the article 'Gas Hot Water Heater Installation', before you decide. It is a job you may be able to do. You could save several hundred dollars.