Water heating is the second-largest energy expense in a home, accounting for about one-fifth of home energy use after heating and cooling, according to the Department of Energy. For Wasatch Front homeowners, the choice matters even more. A federal 2020 survey found that 83% of Utah homes use gas water heating and 15% use electric. Hard water here adds another layer to consider. This guide covers the three main types - tank, tankless, and heat pump - along with efficiency ratings, lifespan, sizing, heat-pump units, gas versus electric, venting, safety and code, hard water and maintenance, 2026 rebates, and price factors.
Key takeaways
- The Department of Energy reports a tanked water heater average life of about 15 years, while ENERGY STAR says tankless water heaters last 20 years.
- The Consumer Product Safety Commission recommends a 120°F setting for water heater temperature.
- Utah requires strapping on water heaters in the upper and lower thirds statewide.
- Hard water causes efficiency loss in gas storage heaters that grows with hardness and use.
- 2026 rebates include ThermWise for gas units and Wattsmart for heat-pump units, available to Rocky Mountain Power customers only.
The three main water heater types
A tanked water heater, also called a storage water heater, holds a ready supply of hot water in an insulated tank. It may be gas or electric. Gas storage tanks use different venting types: atmospheric, direct, power, power-direct, or condensing. Condensing tank models pull more heat from the flue, so their exhaust drops below 130°F. Non-condensing models send exhaust out at 300 to 400°F.
A tankless water heater, as defined by the Department of Energy, stores under 2 gallons of water and has an input above 50,000 Btu per hour. ENERGY STAR says it provides a continuous supply of hot water. It needs a minimum flow to fire, about half a gallon a minute. Its output falls as the temperature rise increases.
A heat-pump water heater, also called a hybrid electric model, moves heat from the room air into the water. It can reach up to four times the efficiency of a resistance model and use up to 70% less electricity. These units come in 40 to 80 gallon tanks. They cool and dehumidify the room they sit in. Most need 240-volt circuits at 30 or 15 amps, though some 120-volt plug-in models exist.
Uniform Energy Factor (UEF) is the efficiency rating used by federal standards and by ENERGY STAR. A higher number means better efficiency.
| Type | Efficiency (UEF) | Life | Needs |
|---|---|---|---|
| Gas storage tank | About 0.60 to 0.99, depends on venting and condensing | About 15 years (Department of Energy) | Metal flue if non-condensing; plastic vent if condensing |
| Gas tankless | About 0.82 non-condensing; 0.95–0.96 condensing | 20 years (ENERGY STAR) | Larger gas line; plastic venting; yearly flushing in hard water |
| Heat-pump | Up to about 4.07 (240 volts); 3.0–3.1 (plug-in) | Not stated by a primary source | Room at 40–90°F; air space; condensate drain |
Efficiency ratings and the 2029 standards
The ENERGY STAR water heater specification version 5.0 took effect April 18, 2023. For gas storage models, the uniform energy factor (UEF) must be at least 0.81, or 0.86 for a high-draw unit. The first-hour rating must be at least 51 gallons. Gas tankless models need a UEF of at least 0.95 and a flow rate of at least 2.8 gallons a minute across a 67°F rise. Heat-pump water heaters require a UEF of at least 3.30 for 240-volt models, 2.20 for 120-volt models, and for split units. Their first-hour rating must be at least 45.
The Department of Energy finalized new standards on April 30, 2024, with a compliance date of May 6, 2029. Under this rule, electric tanked (storage) water heaters over 35 gallons must reach heat-pump-level efficiency. A projection shows heat pumps will make up over half of new electric tanked water heaters, up from about 3%. A separate gas tankless rule was finalized in December 2024 but was disapproved by Congress in 2025 and later withdrawn. There is no new tankless standard.
MYTH: The 2029 standards will ban gas water heaters and tankless models from being sold.
FACT: The 2029 rule applies only to electric tanked water heaters over 35 gallons, and the separate gas tankless standard was withdrawn.
Sizing: First-Hour Rating and Flow
First-hour rating tells you how much hot water a storage heater can deliver in one hour when it starts fully heated. This number depends on tank size, burner or element size, and recovery rate. ENERGY STAR sets minimum first-hour ratings for efficient units: 51 gallons an hour for gas storage models, and 45 for heat-pump models. A 40,000 Btu-per-hour gas tank produces about 81 gallons. A 4,500-watt electric tank delivers about 57 gallons. A 50-gallon heat-pump unit provides about 66 gallons. An 80-gallon heat-pump unit gives about 84 to 86 gallons. Manufacturers list these ratings for each model they sell.
Tankless water heaters are sized by flow at a temperature rise. One common condensing model delivers 5.6 gallons a minute at a 67°F rise. You need at least 0.5 gallons a minute for a minimum flow to activate the heater. In winter, colder incoming water means a bigger temperature rise is needed. A condensing tankless unit can have an input up to 199,900 Btu per hour. A standard atmospheric tank runs about 40,000 Btu per hour. This difference drives gas-line sizing for your home.
Manufacturers publish altitude ratings for their equipment. One common condensing model is rated for 10,100 feet. Higher elevations affect burner performance and may require adjustments. Your installer should verify the unit you choose matches your elevation and incoming water temperature.
Heat Pump Water Heaters in Utah
A heat pump water heater works differently from a standard electric model. Instead of generating heat directly, it moves heat from the surrounding air into the water. ENERGY STAR guidance explains that the unit needs an interior space that stays 40–90°F year-round. The space should have about 1,000 cubic feet of air around the unit. One major manufacturer's minimum is 450 cubic feet. If the room is smaller, ducting kits are available for small rooms. The unit cools and dehumidifies its space. This is a plus in summer but a consideration in winter.
The system has a compressor cutoff temperature. Below that temperature, the unit switches to electric resistance only. ENERGY STAR requires reporting that cutoff. The air around the unit must stay above 37°F for the heat pump to operate efficiently. Most units are 240-volt units running on 30- or 15-amp circuits. Newer 120-volt plug-in models are available with the cord included. These allow a drop-in where no 240-volt circuit exists. The condensate must drain to a floor drain or a nearby sink.
Costs vary by model and installation. We provide a written quote for every job. A rebate is available through Wattsmart for Rocky Mountain Power customers. See the rebates section for current amounts and requirements.
Gas or electric along the Wasatch Front
Utah's water heater market leans heavily toward gas. A federal 2020 survey found 83% of the state's 1.04 million homes use gas water heaters, while 15% use electric. Nationally, the split is closer: 48% gas and 46% electric. Your choice usually follows the existing fuel in your home. Switching fuels means adding a new gas line or a new 240-volt circuit.
The gas utility for most of the region is Enbridge Gas (formerly Dominion Energy). Its rebate program is called ThermWise. The electric utility for most of the region is Rocky Mountain Power. Its program is called Wattsmart. Several cities operate their own electric utility: Bountiful (Bountiful Power), Provo, Lehi, Kaysville, Murray, Morgan, and Brigham City. Wattsmart does not apply in those cities.
Venting, combustion air, and code
Non-condensing gas water heaters produce flue gas between 300 and 400 degrees Fahrenheit. That high temperature requires metal venting. Condensing units, by contrast, exhaust gas under 130 degrees Fahrenheit. Their lower temperature allows PVC Schedule 40, CPVC Schedule 80, approved polypropylene, or stainless steel venting. For common models, maximum vent length with 2-inch pipe is up to 75 feet. With 3-inch pipe, the limit is 150 feet. Condensing heaters create acidic condensate that needs a drain.
For a garage installation, the burner must be at least 18 inches above the floor. The Department of Energy publishes a building guideline citing code on this requirement.
Utah adopts the 2024 plumbing code, the 2024 fuel gas code, the 2024 mechanical code, and the 2021 residential code, with state amendments. These codes became effective July 1, 2026. Permits and inspection are required on any water heater replacement.
Safety: Temperature, Strapping, and Relief
The Consumer Product Safety Commission urges a water heater setting of 120°F. At 150°F, a third-degree burn happens in 2 seconds. At 140°F, the burn time is 6 seconds. At 130°F, it takes 30 seconds. At 120°F, a burn takes about 5 minutes. Most scald injuries and deaths involve the elderly and children under five.
Utah statute, Title 15A, requires every water heater to be anchored or strapped against earthquake movement statewide. The strapping must be placed in the upper third and the lower third of the unit. This requirement includes houses and replaces the residential bracing section. The Utah plumbing code amendment governs relief-valve discharge piping. Follow the manufacturer's instructions, and ensure no more than 180 degrees of turn in the piping.
A water heater pan serves as an emergency receptor only. It is designed for water heater discharge only. The pan drain may connect to a stack.
At 120°F, a child needs about five minutes to receive a third-degree burn.
Hard water, scale, and maintenance
The Water Quality Research Foundation (WQRF) partnered with Battelle on a study of 30 water heaters. The test included 10 gas storage units, 10 electric storage units, and 10 gas tankless units over 90 accelerated days. The gas storage heaters ran on unsoftened water at 26.2 grains per gallon. Their efficiency dropped from 70.4% down to 67.4% at two equivalent years. The loss grows with hardness and with daily use. Scale accumulation reached about 1.16 pounds a year for gas storage, 2.00 pounds for electric storage, and about 0.01 pounds on softened water. Electric storage units showed no efficiency loss because the elements stay submerged, though element life shortens. Gas tankless units on the same water needed deliming after 1.6 equivalent years, with efficiency falling from about 80% to 72%.
Local water hardness varies across the Wasatch Front. Utility reports show Salt Lake City water at 8.0 to 12.4 grains per gallon, with wells reaching up to 33.4. Weber Basin, covering Davis and Weber counties, ranges from 10 to 18 grains. Jordan Valley measures 10, Farmington 8 to 10, and Bountiful is reported as "hard" with no number given. The regional band is roughly 8 to 18 grains per gallon.
A softener changes the math for scale buildup. So does a yearly flush. One tankless manufacturer's instruction calls for flushing deposits at least yearly, a process that takes up to 45 minutes.
2026 Utah Water Heater Rebates
ThermWise is run by Enbridge Gas. The program covers installations from January 1 to December 31, 2026. It is for existing homes only. You need an active Enbridge Gas meter and a GS rate schedule. The rebate for an ENERGY STAR gas storage water heater is $100. An ENERGY STAR gas tankless model qualifies for $300. A condensing ENERGY STAR gas storage unit receives $350. A gas hybrid water heater also gets $350. A smart water heater controller qualifies for $50. The limit is two per measure per household. You must apply within six months of installation.
Wattsmart is offered by Rocky Mountain Power in Utah. A heat-pump water heater qualifies for $350. Any tank size is eligible. You need rate schedules 1, 2, or 3. The rebate applies to existing single-family or manufactured homes. It replaces an electric storage or gas heater. You must apply within 180 days. The offerings changed on February 27, 2026. This rebate is not available in municipal-electric cities. Bountiful is among those cities.
The federal Energy Efficient Home Improvement Credit ended after December 31, 2025. We recommend you check the utility page first before making a purchase. Amounts and conditions change. The figures here are for 2026 and may be different in future years.
What Does This Cost?
The price of water heater work moves up or down based on several factors we check before quoting. Gas-line size matters for tankless units, while a new 240-volt circuit may be needed for heat-pump models. Metal versus plastic venting, a condensate drain, where the unit sits, and the room around it all affect the job. Code items on every replacement include strapping, relief-valve piping, and a pan and drain where required. Removing the old unit, rebate paperwork, and eligibility also factor in. Blue Best quotes an exact price in writing before any work begins.
