Depending on the age and size of your existing hot water heater, replacing it with a tankless model can save you as much as $30 per month in energy costs. Throw in the benefit of never running out of hot water and it is hard not to install a tankless water heater today. There are several things to consider before purchasing a water heater.
Step 1: Find the heater that best suits your needs. Tankless water heaters are rated by the number of appliances they can consecutively produce hot water for. A two-appliance water heater can produce enough water to operate a shower and a sink, but a three-appliance heater can supply hot water to a shower, sink and washing machine all at the same time. Tankless water heaters have a limited number of degrees they can effectively raise the water temperature by. In colder climates where incoming water is icy cold, a larger heater is required to raise the temperature enough to actually make hot water.
Step 2: Finding a location to properly install a tankless water heater can be a challenge. Although the heaters do not weigh too much and can be installed into drywall, plaster, wood or cement, venting constraints and gas supply requirements can be an issue. The heater should be mounted on an outside wall, near the gas and water supply entrances, and in an area that allows at least a foot of clearance around the heater and 2 feet of clearance in front of the heater.
Step 3: Venting a gas-powered tankless water heater requires a 4-inch stainless steel exhaust vent and a 4-inch PVC inlet vent. The vents should be at least 3 inches long but no more than 26 inches in length. Vents need to be a minimum of 3 inches apart and need 2- to 7-feet clearance from things like windows, existing vents and even sidewalks. The cost of the stainless-steel vent pipe should be considered when choosing a location.
Step 4: Gas line length limitations depend on supply line size and can be found in the owner’s manual of each water heater. Hooking up the gas supply to a tankless water heater should be done by a professional. Once attached, the supply will need to be pressure-tested to assure safe and efficient operation.
Following the manufacturer’s instructions is the only way to properly install a tankless water heater.