When considering replacing your conventional hot water heater for a tankless model, one San Diego area plumbing company has some good advice. On conventional water heater vs. tankless, Town and Country Plumbing states on their website that you may save up to $120 a year on energy costs, as you don’t have a burner running constantly. However, most companies who install a tankless water heater will require an annual maintenance visit that generally costs; you guessed it, $120.
In addition, a tankless water heater will usually require installation of a larger gas line and water heater vents as the lines and vents for conventional water heaters are usually smaller. In general, you will likely spend two to three times as much installing a tankless hot water heater over a conventional system, which usually runs just under $1,000.