Aquatherm 150L (Rapid-SS/X4)
Rebates up to
$600
STC $600
Replace-electric, medium household, best zone. Enter your postcode below for exact figures.
VIC Solar Homes rebate
$1,000
50% of installed price, point-of-sale. Stacks with STC/VEEC above.
VIC only. Assumed eligible, not confirmed against the live Solar Victoria product list.
Register data as at CER (STC) 2026-04-30
Specifications
| Type | Integral all-in-one |
| Refrigerant | R417a |
| Tank volume | 150 L |
| Tank material | 304 Stainless Steel |
| Rated heating capacity | 3.6 kW |
| Rated power input | 0.88 kW |
| Hot water delivery | 60 °C |
| Operating ambient | -5 to 45 °C |
| Tank height | 1375 mm |
| Tank diameter | 660 mm |
| Tank weight (empty) | 76 kg |
| Warranty | Tank 15 (pro-rata), all parts 5 |
Certified to
Specs from: Hydrotherm Rapid-SS/X4/OP Specification Sheet (Aquatech Solar Technologies Pty Ltd); public CER SRES register (air source heat pump models).
Certificate rebate by postcode
Registered certificate values
Every scheme this model is registered for, by zone. STCs at $40, VEECs at $85, ESCs at $30 (reference prices as at 2026-07-07). Claim year 2026, medium household.
SRES — STCs (national)
| Zone 1 | 12 STCs | $480 |
| Zone 2 | 12 STCs | $480 |
| Sydney (Z3) | 14 STCs | $560 |
| Melbourne (Z4) | 15 STCs | $600 |
VEU — VEECs (Victoria)
Not yet registered for VEECs.
ESS — ESCs (NSW)
Not yet registered for ESCs.
Certificate counts are computed from the model's registered performance data using the current regulated equations. A lodged claim depends on the specific installation, household size, and the scheme rules in force at creation. Energy savings % is against the AS/NZS 4234:2021 reference electric storage water heater for that zone, medium household, calculated from the model's registered performance data.
The Aquatherm Rapid/X4 is an all-in-one heat pump water heater with an integrated 150 L, 304 grade stainless steel tank, aimed at replacing 125-250 L electric storage systems. It is engineered by Aquatech Solar Technologies Pty Ltd and sold in the Australian market under the Hydrotherm brand, with “Aquatherm” appearing as a separate registered brand string on the CER air source heat pump models list for the same physical unit.
The Panasonic rotary compressor with R417a refrigerant delivers a rated heating capacity of 3.6 kW at 0.88 kW input power, recovering the tank in around 2.1 hours. The unit operates from -5 to 45 degrees C ambient and delivers hot water up to 60 degrees C. It carries a 15 year pro-rata tank warranty and a 5 year full-replacement parts warranty.
The Rapid-SS/X4/C and Rapid-SS/X4/OP register codes (continuous and off-peak/shoulder tariff wiring variants) cover this same physical product. “RS-3.6FA/150L” is grouped in here as well: it carries the identical 150 L tank volume and 3.6 kW rated heating capacity, consistent with an alternate/legacy register code for the same unit, though no manual was found that explicitly cross-references the two code sets.
Registered model codes
Rapid-SS/X4/C, Rapid-SS/X4/OP, RS-3.6FA/150L
Homeowners
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