Posted on: 5 January 2016Share
The primary challenge of designing and building a tiny house is maximizing available space. The average tiny house is about 186 square feet, which doesn't leave a lot of room for things like hot water tanks. While tankless water heaters are a good option for this type of home, the diversity of options can make it difficult to choose the right one. Here are two main things to consider when picking a tankless water heater for your tiny home.
Possibly the major challenge you'll face when choosing a tankless water heater is determining the type of energy it will use to heat the water. You can purchase water heaters that use electricity, natural gas, or propane.
For most homeowners electricity is probably the easiest to use since you simply plug the machine into a socket and go on your merry way. However, electricity is a complex problem for mobile tiny home users. You may not always have access to the electrical grid while on the road, which can mean cold showers during times when you don't.
If you use solar panels to generate electricity for your tiny home, you need to account for the amount of power the tankless water heater will draw, which can average around 9.3 kWh per day (approx. 9,300 watts). For comparison, one solar panel can produce 250-270 watts of power, so you would need a fairly substantial setup just to power your water heater.
Although this is not an issue with gas-powered tankless heaters, these appliances have their own challenges. These tanks need to be vented properly to avoid unintentional natural gas or propane poisoning. You'll also have to adequately gauge the amount of gas you need to purchase, which will depend on how much hot water you use. Some tankless heaters require 150,000 to 200,000 BTUs to heat water. A 20-pound propane tank can provide up to 430,270 BTUs of energy.
These numbers are only averages, so shop around to find a device that fits your home's energy setup.
Indoor vs. Outdoor Devices
The other thing you'll want to consider when purchasing a tankless water heater is whether to buy an exterior or interior device. Exterior water heaters are the easiest to install and better for gas-powered devices, since you don't have to worry about ensuring proper venting. However, they can be problematic if you try to use them in cold areas. You'll need to take precautions to prevent water from freezing in the pipes, which can damage the heating mechanism.
Indoor units are better for people who live or travel in cold climes because the risk of freezing is significantly reduced. As noted previously, though, you need to ensure the area where the water heater is installed is properly vented, which may require you to use more space.
For more information about choosing and installing a tankless water heater for a tiny home, contact an HVAC contractor, such as Smedley & Associates, Plumbing, Heating, Air Conditioning.