Tankless installation covers three jobs: replacing an old tankless heater, putting one in a new home, and converting from a storage tank. HomeGuide says a tankless heater costs $1,400–$5,600 on average with installation. Gas runs higher than electric. Conversions cost the most, because the gas line, venting or wiring usually has to change. In Utah, a gas install may qualify for a ThermWise rebate, and replacement is licensed plumbing work.
Three kinds of install
Tankless to tankless. The simplest job. The gas line, vent path and water connections are already there, so the technician matches them to the new unit. It’s a good time to add anything the old install lacked, such as isolation valves.
New construction or addition. The heater goes in with the rest of the plumbing. Sizing and vent routing are planned from scratch.
Tank to tankless. The old tank comes out and the house is adapted for a heater that fires much harder for short bursts. That’s where most of the extra cost comes from.
What installation costs
Here are the national figures, with the components a conversion can add:
| Item | Range | Source |
|---|---|---|
| Tankless heater with installation, overall | $1,400–$5,600 | HomeGuide |
| Gas tankless, unit, labor and changes | $2,100 to $5,600 | HomeGuide |
| Electric tankless, installed | $1,400 to $3,000 | HomeGuide |
| Labor alone | $600–$2,500 | HomeGuide |
| Typical installed project | $1,406–$3,902, average $2,641 | Angi |
| Larger gas supply line | $350–$2,000 | HomeGuide |
| New exhaust venting | $100–$600 | HomeGuide |
| Dedicated electrical circuit (electric units) | $250–$900 | HomeGuide |
| Removing and disposing of the old tank | $75–$500 | HomeGuide |
| Permits | $50–$200 | HomeGuide |
| For comparison: a tank heater, installed | $600–$3,100 | HomeGuide |
We didn’t find a single sourced total for a tank-to-tankless conversion. Add the component lines that apply to your home. HomeGuide notes that old tank-heater vents can’t be reused for a tankless, so new venting is almost always part of a gas conversion.
Salt Lake City estimates (2022)
The only Utah-specific install figures we found are from HomeBlue, dated January 2022. For Salt Lake City, it put a gas tankless heater at $2,500–$3,000 installed, and an electric unit at $1,800–$1,900. Those figures are several years old. Treat them as a rough local reference, not a current quote.
Gas or electric
HomeGuide’s ranges show gas units costing more to install than electric ones. Most of the gap comes from the gas line and venting. Many homes need a bigger gas supply line, because a tankless burner needs much more gas while it runs than a tank does.
Electric units skip the vent and gas line, but need a dedicated circuit, and sometimes more panel capacity. A technician should size the unit, and a licensed electrician should handle any panel work.
The Department of Energy says tankless heaters typically supply 2–5 gallons per minute. That’s the number to size around: how many showers, taps and appliances run at the same time in your home.
Lifespan and efficiency
The Department of Energy says most tankless heaters have a life expectancy of more than 20 years, against 10–15 years for storage tanks. HomeAdvisor says around 20 years with proper maintenance.
On efficiency, the DOE says tankless heaters can be 24%–34% more efficient than tanks in homes that use less hot water. For homes that use a lot, the gain drops to 8%–14%.
Both figures assume the heater is kept clean. In the Battelle lab study, run on unsoftened test water of 26 gpg, tankless heaters fell from 80% to 72% efficiency before they needed deliming. The lifespan guide covers what shortens and extends a heater’s life.
The ThermWise rebate
Enbridge Gas, formerly Dominion Energy, runs the ThermWise appliance rebate program in Utah. It has run ThermWise programs here since 2007.
- Amount: $300 for a gas tankless water heater.
- Requirement: the heater must be ENERGY STAR certified.
- Deadline: the rebate request must be postmarked within six months of the installation date.
- Questions: the ThermWise Rebate Hotline is 1-877-932-0610.
Rebate amounts can change from year to year, so confirm the current terms before you buy. Keep the itemized invoice that shows the model number, in case the rebate request asks for it.
There’s no current federal tax credit to claim. The IRS says the Energy Efficient Home Improvement Credit covered improvements made through December 31, 2025.
Who can install a water heater in Utah
Water heater replacement is licensed work in Utah. The state’s rule on exempt minor plumbing work expressly excludes the installation or replacement of a water heater. Installing or replacing a residential gas appliance also requires certification under Subsection 58-55-308(2). Utah’s licensing law is being restructured from January 1, 2027. After that, the exemption for small projects under $7,000 applies only if the work does not involve an electrical or plumbing system.
The Utah licensing guide explains the rules in plain terms and points you to DOPL. Ask the technician about their license, and whether they’ll pull the permit, when you book.
Add isolation valves and scale protection now
An install is the cheapest time to set the heater up for easy service.
- Isolation valves. Rinnai says isolation valves are strongly recommended, and Noritz says isolation valves are necessary for flushing. Without them, every future flush starts with plumbing work. See the isolation valves guide.
- Scale protection. Navien’s manual says water above 12 gpg requires a softener or PeakFlow. Navien also gives one additional year of labor warranty when a new heater goes in with PeakFlow. The scale prevention page compares softeners, cartridges and built-in options.
Check your water against the model’s limit before you choose. Takagi’s manual caps hardness at 7 gpg for a single-family home. Highland’s water is 14 gpg, and Provo’s runs 10–15 gpg. Your city page lists the local figure.
Questions to ask before the install
- What size unit do you recommend, and how many fixtures can it run at once?
- Does my gas line, vent or electrical circuit need upgrading, and what does that add?
- Is the model ENERGY STAR certified for the ThermWise rebate?
- Will you install isolation valves and pull the permit?
- What does the warranty require for scale and water quality?
If your current tankless is still working but acting up, the repair page may be the better first call. Otherwise, call to book an install quote with a technician who works in your area, from Spanish Fork to Riverton.