# Water heaters

> Tank, tankless and heat pump water heaters. Ask with your Sheet attached: homeowners who’ve done it and verified pros answer, and anyone can read it.

## Before you ask

The size and fuel, the age, the venting, and what it does wrong.

- **Attach your Sheet** so people see your sizes and the math.
- **Your town is enough.** Never your address; check photos for house numbers and plates.
- **Is it safe?** A safety question here goes to pros verified in plumbing, unless you pick another trade. Only they can call it safe or unsafe.

## Water heater replacement

Gas water heater, 4 people: a 50 gal tank (first hour 84 gal) for a busiest hour of 83 gal, a 3″ vent and a 2 gal expansion tank.

What people get wrong:

- **Firing an empty tank.** Power to an electric tank before it’s full burns out the upper element in seconds; a gas tank fired dry is damaged.
- **A reduced or capped relief line.** The relief line runs full size to an open end you can see — no valve, no cap, no threads, no trap.
- **Sizing by the old tank.** The old tank’s gallons don’t say whether it kept up.

[The worked example, every line's math and the code notes](https://studsheet.com/sheets/waterheater) · [Your own sizes in the app](https://app.studsheet.com/p/waterheater)

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## How the community works

- **Open to read** from anywhere, no account needed.
- **Sign in with your email** to ask, answer and vote. No password.
- **The best answers rise:** votes, “worked for me” and a solved mark. Verified pros carry a badge.

Questions? Write to [support@studsheet.com](mailto:support@studsheet.com).