A failed tank cannot wait for a weekend
A tank that is leaking from the body is losing water continuously and can drop hundreds of gallons into a garage, closet or hallway before anyone notices. Shut off the cold water supply at the valve on top of the heater, then cut gas or power. Photograph the damage for your insurer.
Call right away. We can often tell you on the phone whether a same-day replacement is possible and what unit will fit your space. Have the old unit's capacity and fuel type ready if you can see the label.
What a replacement visit involves
- Confirm the match. Capacity, fuel type, venting and space decide the replacement. A larger tank may not fit a closet built for a smaller one.
- Drain and remove. The old tank is shut off, drained and disconnected. The plumber removes it from the property.
- Set and connect. The new heater goes in with new flexible connectors, a code-compliant relief valve discharge and, where needed, an expansion tank.
- Strap, test and inspect. Seismic straps are installed, gas or electric are tested and the permit inspection is arranged.
Tank, tankless or heat pump
Most emergency replacements are like-for-like because they are quick and fit the existing connections. If you have time, the better questions are whether a tankless unit suits your household and what your utility incentives look like.
A tankless heater needs gas supply, venting and often upgrades that make it a longer job. See tankless water heater service and water heater installation for planned work. When the tank has already failed, a like-for-like swap is usually the sound choice, and you can plan the upgrade later.
Heater dead or leaking? Ask about same-day replacement.
Call (650) 860-1670| Option | Speed | Notes |
|---|---|---|
| Like-for-like tank | Fastest | Fits existing connections and venting |
| Larger or smaller tank | Fast | Space and household size decide |
| Tankless | Longer | Gas and venting changes are common |
| Heat pump unit | Longer | Needs space, drainage and power |
What decides the price of a replacement
- The unit. Capacity, efficiency and fuel type change the equipment cost.
- Venting and gas. A direct swap is simple. Moving or upsizing vent or gas lines is not.
- Code items. Seismic straps, relief valve discharge, expansion tank and a permit are part of a correct job.
- Access and haul-away. Stairs, attic closets and tight clearances add time.
- Time of call. Emergency dispatch costs more than a planned visit.
A replacement is the larger purchase, and the warranty on the new unit and on labor is stated at the quote. Ask what the permit and straps cost before you agree. Your insurer may cover the water damage but not the heater.
What Mountain View requires
The Building Division, at 500 Castro Street, states that a permit is required for every water heater installation and replacement and must be obtained before the work begins. It also asks for two seismic straps on the tank, one in the top third and one in the bottom third. Ask any plumber you call whether they pull the permit. We include it in the job.
The Division can be reached at 650-903-6313 or building@mountainview.gov with questions about a specific address.
A replacement is judged against the California Plumbing Code, Part 5 of Title 24, and the City's Building Division inspects it. The state lists the 2025 edition as effective January 1, 2026.
Water Heater Replacement questions
Is emergency water heater replacement available at night in Mountain View?
Yes. The line is open 24/7. A licensed plumber is dispatched, shuts the system down safely and schedules the replacement, often the same day when stock and schedule allow.
Do I need a permit to replace my water heater in Mountain View?
Yes. The City's Building Division states that a permit is required for every water heater replacement and must be pulled before work begins.
What are seismic straps and are they required?
They are two straps that hold the tank to the wall studs so it does not fall in an earthquake. The City's guide asks for one in the top third and one in the bottom third of the tank.
How long does a replacement take?
A like-for-like tank swap is typically a few hours once the unit is on site. Tankless installs or venting changes take longer.
Can I upgrade to tankless when my tank fails?
You can, but the job is longer and may need gas and venting work. Many owners replace the tank now and plan the upgrade.