Tankless Water Heater Gpm Needs

Gpm needed sum of all individual hot water appliance gpm rates which run at same time.

Tankless water heater gpm needs. A good rule to follow is this. The temperature of the water coming into the heater the peak demand for hot water in gallons per minute gpm and the heater s efficiency as indicated by its uniform energy factor found in the product specs. You ll need to raise the incoming water temperature from 40 degrees to 105. If you use less than 41 gallons of hot water per day a tankless heater is 24 34 more efficient than a tank style heater.

Your water heater should be able to supply enough hot water to your home that it can meet daily demand levels within 30 minutes. So you ll need a tankless water heater that can produce at least a 60 degree rise in temperature at 5 2 gallons per minute. Once you have your total flow rate and the required temperature rise you can find the right size tankless water heater for your home. To determine whether a heater will be able to meet a household s needs a plumber looks at three factors.

If you don t have original paperwork or a model number you can use a generic gpm number for your type of fixture. Tankless water heater efficiency is determined by the water flow rates inside your home. The best gas option in this case would probably be rinnai v series. Gallons per minute gpm is the key when it comes to sizing tankless water heaters.

The lowest price you can get for the highest gpm is easily the takagi t h3 dv n that will give you a whopping 10 gpm. You may not need that big of a tankless water heater so make sure you read the whole article. Below we ve highlighted what size water heater you would need in our example of 6 5 gpm at a 63 f temperature rise. Locate this information with gpm estimate charts which are readily available with a quick google search.

This list includes some of the more common problems that people have with tankless hot water heaters but it is not all inclusive. If you use a lot of hot water around 86 gallons per day tankless water heaters are only 8 to 14 more efficient since they are running more often. You ll need to be able to heat at least 5 2 gallons of water. A sink may run.

The answer is simple. You ll need a tankless water heater that can provide a temperature rise of 50 f for about 6 gallons of water per minute. If you don t see the tankless water heater problem you re having here or if you need technical support with your water heater please visit our help desk to schedule an appointment or call us at 866 356 1992.