Water heaters come in two basic styles — tank and tankless heaters. Each different style has its own advantages and disadvantages. In addition, each tank or tankless water heater also comes with different capacities. For a tank water heater, that means the amount of water it can hold and how quickly it can heat that water. For a tankless heater, it means the amount of water it can heat and how quickly it can heat it as the water passes through. The different elements of these types of appliances will determine which one is right for you.
Target Temperature Rise
A tankless water heater heats up water as it passes through the appliance. The tankless water heater does not actually store any water itself. This means you need do to some math to figure out what type of water heater you need. You will need to measure the average temperature of water coming into your house, which changes depending on the time of year and the placement of your pipes. Then, you will need to consider the average target temperature of water. The average temperature for a shower is about 48 degrees Celsius. For washing dishes, the average is about 60 degrees Celsius to most effectively cut through grease. Therefore, if the water coming into your house is 20 degrees and you want to shower at 48 degrees, you need to find electric water heaters online with at least a 28 degree temperature rise.
The flow rate of water is a metric used for tank and tankless water heaters, but it is more useful for tankless heaters. You should measure the amount of water you use at peak water usage throughout the day. You can often find this information on your water bill each month. Then, you will need to find a tankless water heater with a flow rate and a temperature rise that match your peak usage.
The same is true of a tank water heater, but it generally applies to the capacity. You should measure how much hot water you use at your peak time of the day. Then, you should choose a water heater that is at least four or five litres larger than the amount of water you use at peak time.
Litres Per Minute
If you don’t know how many litres of water you use, even during peak time, the water consumed in a shower is usually the second or third most amount of water used in your home. It’s also typically where the most hot water consumed. A shower consumes about eight litres per minute. Therefore, if you want to figure out approximately how much water you use during your peak time, you can multiply the number of people in your house by eight. Then, multiply that number by how long they shower collectively.