A water heater is a household appliance that heats water to a preset temperature. Storage water heaters are typically gas-fired or electric, tankless water heaters are electric, and solar water heaters use energy from the sun. Choosing the right size of water heater for your home is critical to ensure that you have enough hot water to meet your needs. Storage water heaters come in various sizes, and tankless water heaters are available in multiple capacities.
Here are some tips on how to choose the right size water heater for your needs.
Related: Beginner’s guide to water heaters
Consider The First Hour Rating (FHR)
The First Hour Rating determines how much hot water the water heater can deliver in an hour. The FHR is essential when choosing a water heater because it tells you how much hot water it can provide during peak demand. For example, if you have a family of four and you typically use all four showers at the same time in the morning, you’ll need a water heater with an FHR of at least 80 gallons.
You should search for an FHR that can provide at least as much hot water as is required for all concurrent activities during the busiest time of the day. Using the figures below, you can anticipate peak hour consumption and choose the appropriate FHR.
- Working clothes washer: 30 gallons
- Working dishwasher: 14 gallons
- Shaving: 3 gallons
- Washing dishes: 6 gallons
- One person washing hands: 2 gallons
- One person washing hair: 6 gallons
- One person showering or bathing: 20 gallons
Consider The Energy Factor (EF)
When choosing a new water heater, you’ll want to consider the Energy Factor (EF). The EF is a measure of how efficiently the water heater uses energy. The higher the EF, the more efficient the water heater is.
Gas-fired storage water heaters typically have an EF of 0.60 or higher. Electric storage water heaters usually have an EF of 0.95 or higher. Tankless water heaters have an EF that ranges from 0.82 to 0.99. Solar water heaters have an EF of 1.0.
You can find the EF on the water heater’s EnergyGuide label. The label also lists the estimated annual operating cost of the water heater. It can be helpful when you’re comparing the costs of different models.
Size For Tankless Heater
When choosing a tankless water heater, you’ll need to consider the size of the unit. Tankless water heaters are available in a range of sizes. Calculate the required flow rate based on hot water demand and the desired temperature change to choose the best tankless water heater. Your size will depend on the number of bathrooms in your home and the peak hour demand for hot water.
For example, if you have a family of four and you typically use all four showers at the same time in the morning, you’ll need a tankless water heater with a capacity of at least 7.5 gallons per minute (GPM).
If you have a family of four and you typically use two showers and the dishwasher at the same time in the morning, you’ll need a tankless water heater with a capacity of at least 4.5 GPM. You can find the capacity of the tankless water heater on the manufacturer’s website or in the product manual.
Conclusion
When choosing a water heater, it’s essential to consider the size of the unit and the energy efficiency. You should also search for an FHR that can provide at least as much hot water as is required for all concurrent activities during the busiest time of the day. Tankless water heaters are available in various sizes, and you’ll need to choose the size based on the number of bathrooms in your home and the peak hour demand for hot water.
For more information about sizing a water heater, read it here: https://homeinspectioninsider.com/what-size-water-heater-you-need/. Choosing the right size for a water heater might be tricky, so make sure to consult a professional if needed.
