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Tankless vs. Tank Water Heaters

Learn the pros and cons of a tankless water heater and a tank water heater in this Howcast plumbing repair video with expert Tim Flynn.


"I'm Tim Flynn and I'm the owner of Winters Plumbing and Heating in Cambridge, Massachusetts. Winters Company offers plumbing, heating, cooling. If you need service today; we're the business to call. My website is I'll be talking to you today about plumbing.

This is the traditional water heater, most people have them in their homes right now, and its a tank. Its the only vessel in your house that stores water besides the tank on your toilet. So, a tank-type water heater has a lifespan of anywhere in this area from 7-9 years, and so as water comes in, the thermostat turns on, makes the water hot, and shoots it out to the faucets. The water heaters that we have right now with tanks, if a 40-gallon water heater is being used, you're really only going to get about 27-33 gallons of hot water out of that tank, because as hot water goes out, cold water goes in and dilutes the tank full of hot water.

A tank-less water heater is basically like a wall-mounted suitcase, and heats water instantaneously like a jet underneath cold water. So as water passes through this vessel, the heat gets super-heated by gas and it comes out so that you can shower, and then everybody else in your house could shower, and then everybody on the street could shower, without running out of hot water, and you cannot do that on a tank-type water heater.

The efficiencies between a tank and a tankless are also important to know. A tank water heater has about a 62% efficiency, so 62% of every dollar that you're going to spend is going to go towards making that water hot. As opposed to a tankless water heater, they're about 92-95% efficient, so you get more bang for your buck with a tankless water heater."

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