Pentair UltraTemp Heat Pumps — Inverter Heating and Chilling from 9 kW to 135 kW
The Pentair UltraTemp range covers water heating and chilling for aquaculture, aquaponics and commercial water temperature control — from compact 9 kW units through to 135 kW commercial systems. Every model in the range uses a full-inverter compressor that modulates output to match the actual heating or cooling load (rather than cycling on and off), a titanium heat exchanger rated for fresh, brackish and salt water, and R32 low-GWP refrigerant. All units both heat and chill.
Fresh by Design is an authorised Pentair supplier across Australia and New Zealand. We size each unit against your water volume, target temperature, ambient conditions and power supply — talk to us before settling on a model.
Key Features
- Full-inverter compressor and variable-speed fan — output follows the load instead of cycling on/off, which cuts running cost and holds water temperature stable
- Titanium heat exchanger — fresh, brackish or salt water
- Heats and chills, with automatic defrost
- R32 refrigerant (low global warming potential)
- Colour LCD touchscreen; Wi-Fi remote monitoring and control via the Pentair app (module included on HXi, optional on VXi)
- VXi series: hydrophilic evaporator coating and filter dryer
- 15-year warranty on HXi and VXi models (terms and conditions apply)
Which UltraTemp series do I need — HXi, VXi or Commercial?
It comes down to capacity and installation clearance. The HXi (9–35 kW) discharges air sideways, so it suits installations with limited overhead clearance — under eaves, beside sheds, in plant rooms with low ceilings. The VXi (13–32 kW) discharges air vertically and needs open space above, but tolerates tighter side clearances. For larger loads, the Commercial PWT series (68 and 135 kW) covers recirculating aquaculture systems (RAS), hatcheries and other facilities with substantial continuous heating or chilling demand.
| Series | Capacity | Fan discharge | Power supply | Typical installation |
|---|---|---|---|---|
| HXi | 9.0–35.1 kW heat / 3.2–14.6 kW chill | Side (horizontal) | Single phase to 24 kW; three phase 28 & 35 kW | Limited overhead clearance |
| VXi | 13.5–32.0 kW heat / 6.2–14.8 kW chill | Top (vertical) | Single phase to 28 kW; three phase 32 kW | Open overhead space, tight side access |
| Commercial (PWT) | 68 & 135 kW heat / 28 & 50 kW chill | Top | Three phase 400–415 V | RAS, hatcheries, large facilities |
UltraTemp HXi — Side Fan Inverter (9–35 kW)
| Model | Heating Capacity | Cooling Capacity | Flow Rate (LPM) | Power Supply |
|---|---|---|---|---|
| UTHP-9-HXi | 9.0 kW | 3.2 kW | 53 | Single Phase |
| UTHP-12-HXi | 12.0 kW | 3.8 kW | 66 | Single Phase |
| UTHP-16-HXi | 16.0 kW | 5.6 kW | 86 | Single Phase |
| UTHP-20-HXi | 20.0 kW | 7.9 kW | 100 | Single Phase |
| UTHP-24-HXi | 24.3 kW | 8.9 kW | 141 | Single Phase |
| UTHP-28-HXi | 28.2 kW | 11.8 kW | 158 | Three Phase |
| UTHP-35-HXi | 35.1 kW | 14.6 kW | 230 | Three Phase |
UltraTemp VXi — Top Fan Inverter (13–32 kW)
The VXi adds a hydrophilic evaporator coating (corrosion protection, quieter airflow) and a filter dryer that keeps ice and dirt out of the refrigerant circuit.
| Model | Heating Capacity | Cooling Capacity | Flow Rate (LPM) | Power Supply |
|---|---|---|---|---|
| UTHP-13-VXi | 13.5 kW | 6.2 kW | 108 | Single Phase |
| UTHP-17-VXi | 17.5 kW | 6.9 kW | 133 | Single Phase |
| UTHP-20-VXi | 20.6 kW | 12.2 kW | 158 | Single Phase |
| UTHP-24-VXi | 24.0 kW | 13.5 kW | 167 | Single Phase |
| UTHP-28-VXi | 28.0 kW | 14.5 kW | 200 | Single Phase |
| UTHP-32-VXi | 32.0 kW | 14.8 kW | 250 | Three Phase |
Commercial Series — High-Capacity Inverter (68–135 kW)
| Model | Heating Capacity | Cooling Capacity | Power Supply | Notes |
|---|---|---|---|---|
| PWT-HP-68i | 68 kW | 28 kW | Three Phase 400–415 V | In stock |
| PWT-HP-135i | 135 kW | 50 kW | Three Phase 400–415 V | 8–12 week lead time |
Heating capacities at 27 °C ambient / 26 °C water; cooling capacities at 35 °C ambient / 30 °C water (Pentair rated conditions). Capacity and COP vary with ambient temperature — full performance curves are in the spec sheets under Downloads.
What size heat pump do I need?
Sizing depends on water volume, target temperature versus your coldest (or hottest) ambient, whether tanks are indoors or covered, and your flow rate and power supply. A unit that is marginal at winter ambient will run flat out and still fall short — and chilling capacity is roughly a third to half of heating capacity on the same unit, so chill-driven systems are sized differently. Send us your volume, target temperature and location and we’ll match a model: call 02 4868 2500 or email sales@freshbydesign.com.au.
Applications
Suitable for fresh water, seawater and brackish systems: RAS, aquaponics, hatcheries, broodstock conditioning, live holding and purging, research aquariums, and commercial pools. Pairs with our titanium plate heat exchangers where indirect heating is required. Browse the full Heating & Cooling range for related equipment.
Downloads
- UltraTemp Inverter Heater Brochure (PDF)
- UltraTemp VXi Technical Data Sheet (PDF)
- UltraTemp HXi Owner’s Manual (PDF)
- UltraTemp VXi Owner’s Manual (PDF)
- PWT Commercial Heat Pumps Brochure (PDF)
- Wi-Fi Module Manual (PDF)
Frequently Asked Questions
| What is the difference between the HXi and VXi series? | Fan direction, mainly. The HXi discharges air from the side, so it fits under eaves and in low-clearance plant rooms; the VXi discharges from the top and needs open space above. The VXi also adds a hydrophilic evaporator coating and a filter dryer. Capacity ranges overlap (HXi 9–35 kW, VXi 13–32 kW), so most buyers choose on installation constraints. |
| Can it be used for aquaculture and salt water? | Yes. The titanium heat exchanger handles fresh, brackish and salt water, and the heat/chill function covers both winter heating and summer cooling of culture water. We supply these units into RAS, aquaponics and hatchery systems across Australia and New Zealand. |
| What is the warranty? | HXi and VXi models carry a 15-year warranty (terms and conditions apply). Ask us for the warranty terms for the commercial PWT models when requesting a quote. |
| Does it support remote monitoring? | Yes — a colour LCD touchscreen is standard, and the Pentair Wi-Fi module enables monitoring and control from a smartphone app (included on HXi models, optional on VXi). |
| What refrigerant does it use? | R32, which has a lower global warming potential than older refrigerants such as R410A. |
| Single phase or three phase? | Single-phase models run up to 24 kW (HXi) and 28 kW (VXi). Three-phase models: HXi 28 and 35 kW, VXi 32 kW, and both commercial units (68 and 135 kW, 400–415 V). |
