H2O VAULT 300L (H2O-300/N6D1)
Rebates up to
$1,580
STC $680 · VEEC $850 (VIC) · ESC $900 (NSW)
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.
AS/NZS 4234 energy savings
83%
vs the standard's reference electric storage water heater, medium household, best zone.
Register data as at CER (STC) 2026-04-30 · VEU 2026-07-01
Specifications
| Type | Integral all-in-one |
| Refrigerant | R290 |
| Tank volume | 300 L |
| Tank material | Enamel-lined steel tank, galvanized steel outer casing, polyurethane insulation |
| Rated power input | 0.48 kW |
| COP | 5.21 (Inlet water 14 to 55 degrees C; air 19 degrees C DB / 15 degrees C WB) |
| Sound level | 49 dB(A) |
| Operating ambient | -10 to 43 °C |
| Tank height | 2010 mm |
| Tank diameter | 640 mm |
| Electric backup | 2 kW |
| Warranty | 5 years (product; excludes plumbing accessories) |
Certified to
Specs from: H2O VAULT Product Datasheet (2024 version); public CER SRES / VEU / ESS registers.
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 | 13 STCs | $520 |
| Zone 2 | 13 STCs | $520 |
| Sydney (Z3) | 16 STCs | $640 |
| Melbourne (Z4) | 17 STCs | $680 |
| Canberra (Z5) | 17 STCs | $680 |
VEU — VEECs (Victoria)
| Zone | Repl. electric metro / regional | Repl. gas | Energy savings |
|---|---|---|---|
| Melbourne (Z4) | 9 / 10 | 9 | 82.9% |
| Canberra (Z5) | 9 / 10 | 8 | 81.4% |
ESS — ESCs (NSW)
| Zone | Repl. electric metro / regional | Repl. gas metro / regional | Energy savings |
|---|---|---|---|
| Sydney (Z3) | 28 / 29 | 14 / 14 | 76.8% |
| Canberra (Z5) | 29 / 30 | 14 / 13 | 72.8% |
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 H2O VAULT 300L (H2O-300/N6D1) is an all-in-one heat pump water heater with a 300 L tank, sized for 4+ person households or paralleled for larger demand. The heat pump module sits atop the tank in a single cabinet, with a microchannel condenser coil wrapped around the tank rather than a separate water loop, and uses R290 refrigerant. The unit measures 640 mm diameter by 2010 mm high.
At the manufacturer’s rated test condition (inlet water 14 to 55 degrees C, air 19 degrees C DB / 15 degrees C WB), the unit returns a COP of 5.21 with an average heat pump input power of 480 W, the higher-efficiency unit in the H2O VAULT range. It operates across an ambient range of -10 to 43 degrees C and carries a sound pressure level of 49 dB(A). A 2.0 kW electric backup element is fitted.
The inner tank is enamel-lined steel over a galvanized steel outer casing with polyurethane insulation and a magnesium anode for corrosion protection. The product carries WaterMark certification and a 5-year warranty (excluding plumbing accessories). The same model code H2O-300/N6D1 appears on the STC, VEU, and ESS registers.
Registered model codes
H2O-300/N6D1
Homeowners
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