Tankless water heaters are an energy-efficient, space-saving option for homeowners looking to upgrade their hot water system. Unlike standard tank units that store and heat a tank of water, tankless models heat water on demand, ensuring a continuous supply. However, choosing the right size is essential to ensure you have a sufficient hot water supply to satisfy your household needs.
In this guide, the water heater experts at Universe Home Services explain the factors that determine the ideal size for your tankless system and how to calculate the right unit for your specific needs.
Sizing a Tankless Water Heater: Considerations
When choosing a tankless water heater, there are several factors to keep in mind, including:
- Household size: The number of people in your home significantly impacts hot water demand. A family of four will require a larger unit than a single-person household.
- Simultaneous usage: Consider how many appliances and fixtures you use at the same time. For example, running a shower and dishwasher simultaneously increases the demand.
- Flow rate: Tankless water heaters are measured by their flow rate, which is how many gallons per minute (GPM) they can heat. Larger homes with multiple bathrooms will need a higher GPM rating.
- Incoming water: The colder your incoming water, the harder the water heater must work to reach the desired temperature. This can be particularly challenging during cold Long Island winters.
- Fuel type: Gas-powered tankless water heaters typically provide higher flow rates than electric models, making them ideal for larger households.
How to Size a Tankless Water Heater
To determine the correct size for your home, follow these steps:
Calculate Your Peak Hot Water Demand
Identify the maximum number of fixtures and appliances that could be used simultaneously and add up their flow rates in GPM. Common flow rates typically include:
- Shower: 2.5 GPM
- Kitchen sink: 1.5 GPM
- Dishwasher: 1.5 GPM
- Washing machine: 2.0 GPM
If you expect to run a shower, kitchen sink, and dishwasher simultaneously, your peak demand would be around 5.5 GPM.
Determine the Temperature Rise
Find the difference between your incoming water temperature and your desired hot water temperature. For instance, if your groundwater temperature is 50º F and you want 120º F water, your unit needs to provide a 70º F temperature rise.
Choose a Unit with the Right Flow Rate & Temperature Rise Capability
Based on your calculations, select a tankless water heater that meets or exceeds your peak demand while providing the necessary temperature rise. After completing the steps above, if you’re unsure which system is ideal for your needs, trust a professional water heater technician to determine the best solution for your household.
Professional Tankless Water Heater Installation & Replacement
Choosing the right size tankless water heater is essential for maintaining comfort and efficiency in your home. At Universe Home Services, our professional plumbers have the expertise to assess your household’s hot water needs and recommend the best unit for you. Whether you’re upgrading to a tankless system for the first time or replacing an old unit, we offer expert installations and reliable service to ensure optimal performance.
Contact Universe Home Services today to schedule a consultation and enjoy endless hot water with a perfectly sized tankless water heater.