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Serving Staten Island's Heating and A/C needs since 1950


How Do I Know What Size Water Heater to Get?

water-heater-in-cornerNo matter the season, you need hot water for your house. If you’ve ever lost hot water in your home for a day, you already know how miserable and unpleasant life can get. Almost as bad as having no hot water is having a water heater that isn’t the correct size for your needs. A water heater that’s too small won’t supply your household with the necessary hot water. A water heater that’s too large will cost a small fortune to run.

So how you do you find an ideal new water heater in Staten Island, NY?

It’s not hard: call our professionals! You shouldn’t attempt to first purchase a replacement water heater, or the first one for a new home, and then call plumbers. Let them help you choose the water heater. They’ll make professional calculations to determine the idea size and type of system.

We’ll show you what we do to size water heaters below.

For storage tank water heaters …

The most common type of water heater in homes is the storage tank water heater, which keeps a supply of water heated up and ready for use, but which can also have the water supply depleted through high demand.

Sizing a tank water heater requires the professionals know two important pieces of information: the first hour rating and the peak hour demand. The first hour rating is the number of gallons of how water a tank water heater can supply in an hour if it starts with a full tank. The first hour rating for a water heater combines other stats: the capacity of the tank, whether it uses gas burners or electric heating elements, and how powerful the burners or heating elements are.

Peak hour demand is the gallons used during the hour of the day when there’s the greatest hot water demand in the household. It’s usually during the morning, when people are showering, shaving, brushing teeth, etc. This number of gallons determines the first hour rating of the system. If you have a peak hour demand of 36 gallons, the professionals will recommend a unit with a 34 to 38 first hour rating.

For tankless water heaters …

A tankless water heater doesn’t store water at all. Instead, it activates its burners or electric heating elements to warm water as it is needed. Because of this different type of operation, tankless systems have their own sizing criteria: maximum temperature rise at a given flow rate.

The flow rate measures how many gallons per minute the appliances in the house use. Specifically, the appliances that may be used at the same time. Too many taps on at once can overwhelm a tankless system that isn’t properly sized.  The maximum temperature rise is how much the water temperature must be raised from when it enters the water heater to when it reaches taps. For example, if you want the water temperature at the taps to be 120°F and the water enters the water heater at 50°F, the temperature rise for the unit should be 70°F.

If you’re looking for a new water heater installation, trust to our professionals to find the right match for your house.

Bob Mims Heating & Air Conditioning: Serving Staten Island’s Heating and A/C needs since 1955.

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