Follow us on

In this video, This Old House plumbing and heating expert Richard Trethewey helps a homeowner be proactive about their home maintenance by replacing their existing tank-type water heater before it fails.

SUBSCRIBE to This Old House:

Plumbing and heating expert Richard Trethewey takes us on a house call to relieve a homeowner’s stress. With a 16-year-old water heater lurking in the basement, the homeowner is expecting it to fail at any moment, so Richard suggests they swap it out with a new unit.

Difficult: ⅖
Time: 4 hours
Cost: Under $800

Where to find it?
Richard installs a hot water heater (tank-type) with the help of a homeowner. Richard suggests replacing the old hot water heater with a new tank instead of opting to install a new combination boiler, as it’s the most cost effective solution, and a really simple replacement. Richard suggests that once the new hot water heater reaches the end of its life, the boiler will likely be at the end of its life too. At that point, replacing both the boiler and how water heater with a combination boiler is the best solution.

Tools and materials are manufactured by Rheem Manufacturing [

To remove the old tank use the following steps:
1. Shut off the gas line and close the water lines connected to the tank.
2. Drain the water out of the tank. There’s a discharge point in the tank that Richard can connect a
hose to drain out the water. (If there isn’t a nearby utility sink or a floor drain on the basement level,
you’ll need to pump the water up to the grade and discharge outside.)
3. Unthread the gas connection with a pipe wrench.
4. Using a pipe cutter, cut the water lines both to and from the tank.
5. The final connection to the hot water heater is the flue pipe, which can be cut with a reciprocating

To install the new tank use the following steps:
1. Using new ductwork, reconnect the flue pipe to the chimney and seal it with silicone.
2. At the disconnect points, push connect new 1⁄2” copper pipes from the shutoff valves to supply
valves on the tank. The main line should go in on the right and the hot water line should leave on the
3. Rethread the gas piping on the bottom of the tank using the pipe wrench. Some pipe dope will
ensure the gas pipe stays fully sealed.
4. Turn the gas back on and check for leaks.
5. Turn the water on and let it fill the tank.

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:

Permanent marker [
Plumber’s sanding cloth [
Shims [
Plumber’s thread tape [
Various copper fittings [
Concrete [
Lead-free solder [
Flux [
Vacuum valve [
Self-tapping chimney screws [

Water pump pliers [
Garden hose and pump (optional) [
Screwdriver [
Tubing cutter [
Pipe wrenches [
Bubble level [
Cold chisel [
Hammer [
Trowels [
Pipe brushes [
Gas torch [
Screwgun [

Plus, download our FREE app for full-episode streaming to your connected TV, phone or tablet:

About Ask This Old House TV:
From the makers of This Old House, America’s first and most trusted home improvement show, Ask This Old House answers the steady stream of home improvement questions asked by viewers across the United States. Covering topics from landscaping to electrical to HVAC and plumbing to painting and more. Ask This Old House features the experts from This Old House, including general contractor Tom Silva, plumbing and heating expert Richard Trethewey, landscape contractor Jenn Nawada, master carpenter Norm Abram, and host Kevin O’Connor. ASK This Old House helps you protect and preserve your greatest investment—your home.

Follow This Old House:

How to Replace a Tank-Type Water Heater | Ask This Old House


1923 , [vid_dislikes]
This Old House,Home Improvement,DIY,Construction,Ask This Old House,Building,water heaters,plumbing,heating,Richard Trethewey