If you’re in the market for a new hot water heater, you might be considering one of the newer tankless models. These models are definitely more energy efficient than their traditional tank counterparts, but there are some things to keep in mind as you make your decision.
Traditional hot water heaters store water in a large tank. Your natural gas or electricity is then called upon to heat this water to your preset temperature. When hot water is used, the tank refills, and the heating process begins again. If you don’t use any hot water for a few hours, the water in the tank cools and has to be reheated. This process of heating and reheating unused water is what makes older tank models less energy efficient than tankless versions. Tankless hot water heaters are able to heat water on demand. You turn on hot water anywhere in the house, and water is pulled through the tankless heater and heated on its way through the heater to your faucet. This reduces energy consumption by only heating water when you actually “ask” for it. It also ensures that you’ll never run out of hot water in the middle of a shower again.
The problem that arises for most people when it comes to tankless hot water heaters has to do with misconceptions about their abilities. Many people confuse tankless water heaters with point-of-service units. Tankless water heaters do, indeed, offer the energy efficiency described above, but cannot deliver hot water to your faucets any quicker than your old tank model water heater. The distance between your faucet and the hot water heater is what determines how long you have to wait for hot water to get to where you are. Point-of-service water heaters are installed at multiple water-delivery points in your home. They work like tankless heaters in that the water isn’t stored in a tank and can be heated on demand. They are able to deliver hot water to their respective faucets practically instantly since the water doesn’t have to travel far. If you’re looking for instantly delivered hot water at any faucet in the house, you’ll want to invest in point-of-service units.
Another difference between tankless models and point-of-service units has to do with how many hot water applications you can run at once. Typically, a lower-end tankless hot water heater won’t be able to power any more simultaneous applications than your old tank heater. This is because there’s a definite limit to how much water can be processed by the tankless water heater at once. It doesn’t mean that one application will run out of hot water, but it does mean that one or more of the simultaneous applications will see reduced water pressure. Point-of-service heaters obviously make it possible for you to run every hot water application in the house that has a unit attached since the water isn’t being run through a single source.
Your next consideration should be how much water a tankless model can process in terms of gallons per minute (GPM). To give you an idea of what size tankless heater you’ll need to run as many applications as you’d like, here’s a list of average GPM rates: shower and kitchen faucet–2.5 (each), bathroom faucet–2.2, washing machine and dishwasher without independent heating–2 to 3 (each). Many newer models of each of these have lower rates, so your GPM needs could be lower. Based on the numbers above, you’ll need a tankless water heater capable of delivering 5 GPM if you want to be able to run two showers at once without any loss of water pressure. If you aren’t able to find a single model that meets your needs in terms of GPM, it is possible to have two (or more) units installed and running parallel to one another.
The least expensive tankless models are electric, but there are natural gas models available, too. Check out top rated tankless water heaters for reviews, including pros and cons, of several tankless models. You’ll also find some great tips for finding the right unit for you as well as installation guidelines and estimates.