A combined heating system
Phoenix and Scottsdale pool owners often ask whether to choose a gas heater or an electric heat pump for cooler-season swimming. The Pentair UltraTemp ETi hybrid puts both types of heating in one unit. That flexibility is useful to discuss when you want different heating approaches for different days or swimming plans. It also means the home and equipment pad need to support both energy sources.
Garrett's short version: the ETi gives you four ways to run one heating system. Start with how you use the pool or spa, then have the gas supply, electrical service and installation location checked before deciding whether it fits.
What is the UltraTemp ETi?
The UltraTemp ETi is a specific Pentair hybrid product. It is not the same as the standard UltraTemp electric heat pump or a standalone MasterTemp gas heater. Pentair pairs an air-source heat pump with a gas-fired heater in the ETi cabinet. Pentair lists natural-gas and propane versions; the selected model must match the property's fuel source. Its product literature says the fuel versions are factory-configured and cannot be converted from one gas type to the other in the field.
The heat-pump side moves heat from outdoor air into the circulating water. Its performance changes with air and water conditions. The gas side burns fuel to add heat. The two technologies offer different ways to meet a temperature goal; neither promises a particular warm-up time or utility bill for every Phoenix property.
Four modes, in plain language
Pentair's ETi installation and user's guide describes these modes:
Hybrid and Dual are different. Hybrid mode manages heating using the selected temperature difference and time period; Dual mode runs both heat sources together. The exact results depend on the unit settings, outdoor conditions, pool size and target temperature. Ask the installer to explain the controls for the selected model and how they will be set for your household.
| Mode | What it means | Question to ask |
|---|---|---|
| Heat Pump Only | The electric heat pump supplies the heat. | Can it meet your desired temperature and timing under the conditions when you swim? |
| Gas Only | The gas-fired section supplies the heat. | Is the property's gas service sized for this load alongside other appliances? |
| Hybrid | The unit chooses between heat-pump and gas operation according to its settings and heating demand. | How should those settings match your actual swim schedule? |
| Dual | The heat pump and gas section run together. | When would faster heating justify using both energy sources? |
Where the Phoenix decision starts
On a mild day, a heat pump may be a practical way to add heat over a longer period. When you want a faster temperature change for a planned swim, gas operation may matter more. Cooler nights also increase the importance of heat loss between uses. A properly chosen cover may help retain heat, but it does not replace a heating assessment.
The important questions are concrete: Which months do you swim? Is the pool kept warm regularly, or heated for specific days? Is there a separate spa, and how is it plumbed? What temperature do you start from and want to reach? Our gas-versus-heat-pump guide helps frame that comparison before you consider the combined unit.
A hybrid still needs two utility checks
Putting both heating methods in one cabinet does not remove their supply requirements. A qualified assessment needs to look at the available electrical service and panel capacity, the correct circuit for the exact model, and the existing gas meter, line and other household gas loads. The equipment location, airflow, clearances, water flow and plumbing also need review against Pentair's guide and local requirements. Do not use a generic panel size, breaker number or gas-meter label as a go/no-go answer for your home.
Our electrical-service guide and gas-meter guide explain what information to gather. The ETi uses both sides of that checklist. Haoly Pools is a Pentair authorized installer; we can discuss the product and coordinate a site-specific equipment review. Installation decisions belong with qualified professionals and the exact Pentair instructions.
When to put ETi on the shortlist
Ask about the UltraTemp ETi when you value the option to operate as a heat pump, as a gas heater or in one of its combined modes, and the property may be able to support both utilities. Also ask for a comparison against separate equipment and your current system. A hybrid may offer useful flexibility, but its purchase and operating fit depends on your pool, use pattern, energy prices and installation work. We would not promise that its most efficient-sounding mode is automatically the least expensive for every swim.
If you are planning cooler-season swimming in Phoenix or Scottsdale, tell Haoly Pools about your pool and schedule. We can start with your goals and the existing equipment, then identify which supply and product questions need an on-site answer.
Is UltraTemp ETi the same as UltraTemp?
No. UltraTemp is Pentair's heat-pump family. UltraTemp ETi is a hybrid unit with both a heat pump and a gas-fired section. Confirm the exact model on any proposal.
Does Hybrid mode run gas and the heat pump at the same time?
Hybrid mode uses control logic based on the selected temperature difference and time period. Dual mode runs both heat sources together. Ask the installer to explain how the selected settings affect operation.
Can I choose natural gas now and switch the ETi to propane later?
Pentair lists separate natural-gas and propane versions and says they are not field-convertible. Choose the model that matches the verified fuel supply.
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