Ask This Old House plumbing and heating expert Richard Trethewey heads to Milwaukee to install an instantaneous water heater. SUBSCRIBE to This Old House: http://bit.ly/SubscribeThisOldHouse Richard installed an RUR Super High Efficiency Plus instantaneous hot water heater [https://amzn.to/2JxgPk3], manufactured by Rinnai [https://www.rinnai.us/]. Cost: $2000 Skill Level: Expert Tools List for Installing a Tankless Water Heater: Pipe wrench [https://amzn.to/30C1bcN] Drill [https://amzn.to/2xMFxWQ] Hole saw [https://amzn.to/2JuwyjA] Shopping List: 1” gas line and fittings [https://amzn.to/2XN1e3E] 4” PVC pipe and fittings [https://amzn.to/2XO6Pa1] PVC glue [https://amzn.to/2Jy9wsd] Teflon tape [https://amzn.to/2xQB45f] copper pipe and fittings [https://amzn.to/2JxhRwo] Pipe cutter [https://amzn.to/30vgHa5] Steps: 1. An installation like this that involves gas piping is best left to a licensed, professional plumber. 2. Shut off the water and the gas to the hot water tank. Drain the water out of the tank and remove the old tank. 3. The new water heater may require a larger gas line, which will need to be run from the gas meter to the water heater. 4. Using the hole saw, drill a hole on the outside of the house near the location of the water heater. Run PVC pipes for the fresh air intake and vent through that hole. 5. Connect the cold water supply line to the water heater and the hot lines out of the heater using the _” copper pipe. 6. An on-demand water heater requires an electrical outlet.  An electrician may need to assist in adding one near the installation location. 7. A cross-over valve can be installed at the furthest plumbing fixture to allow the built-in recirculation pump to keep hot water at the ready. 8. Turn on the cold water supply, gas supply, and power to the water heater and test. Resources: Expert assistance for this project was provided by Budiac Plumbing & Heating, Inc of Milwaukee, WIsconsin. About Ask This Old House TV: Homeowners have a virtual truckload of questions for us on smaller projects, and we're ready to answer. Ask This Old House solves the steady stream of home improvement problems faced by our viewers—and we make house calls! Ask This Old House features some familiar faces from This Old House, including Kevin O'Connor, general contractor Tom Silva, plumbing and heating expert Richard Trethewey, and landscape contractor Roger Cook. Looking for more step by step guidance on how to complete projects around the house? Join This Old House INSIDER to stream over 1,000 episodes commercial-free: https://bit.ly/2GPiYbH Plus, download our FREE app for full-episode streaming to your connected TV, phone or tablet: https://www.thisoldhouse.com/pages/streaming-app Follow This Old House and Ask This Old House: Facebook: http://bit.ly/ThisOldHouseFB Twitter: http://bit.ly/ThisOldHouseTwitter http://bit.ly/AskTOHTwitter Pinterest: http://bit.ly/ThisOldHousePinterest Instagram: http://bit.ly/ThisOldHouseIG http://bit.ly/AskTOHIG For more on This Old House and Ask This Old House, visit us at: http://bit.ly/ThisOldHouseWebsite How to Install a Tankless Water Heater | Ask This Old House null