Davey RainBank Submersible Rainwater Harvesting Kit - In-Tank Pump, Mains Backup, WaterMark NZ

The Davey RainBank submersible kit places the pump inside your rainwater tank for quieter running and a cleaner installation — no external pump to house or protect. The pump cannot be tampered with by children or pets. The system automatically uses rainwater first and switches to mains water when the tank is empty.

A float switch inside the tank detects water level. When water is present and demand is detected, the submersible pump delivers rainwater. When the tank runs dry, mains water flows through the RainBank without the pump running. Mains continues to flow even in a power outage.

A built-in dual check valve meets the backflow protection requirements of AS/NZS 3500-1. No solenoid valves in the design.

Available in five models from small single-tap applications through to double storey homes. Two models are available with a 20-metre pump lead for deeper tanks. Select your model from the dropdown.

WaterMark WMTS-477:2016 (Lic WM-022042). Smart Approved WaterMark. Tested in compliance with AS/NZS 4020. Must be installed by a licensed plumber.

Bore water quality varies significantly. We recommend testing your bore water before selecting a filtration system — get in touch and we'll help you choose the right configuration for your supply.

Key specs at a glance

• Type: Submersible pump dual source rainwater harvesting kit
• Float type: Submersible float (integral to pump, inside tank)
• Max mains water pressure: 900 kPa
• Max pump pressure: 600 kPa
• Max water temperature: 50°C
• Mains inlet: ¾" BSP M | Rainwater inlet: 1" BSP M | Outlet: ¾" BSP M
• Controller: IP23, 220–250V, 50Hz
• Backflow protection: Built-in dual check valve (AS/NZS 3500-1)
• WaterMark WMTS-477:2016 (Lic WM-022042)
• Guarantee: 3 years

Choosing your model

KRBSA1 — for 1–2 taps or light irrigation
Pump: D23A/B submersible | Flow @ 200 kPa: 10 lpm | Output: 0.20 kW
For minimal demand — a single toilet, outdoor tap, or small irrigation zone.

KRBS1 — for single storey homes
Pump: D42A/B submersible | Flow @ 200 kPa: 40 lpm | Output: 0.60 kW
Suits single storey homes with standard simultaneous demand.

KRBS1/20 — for single storey homes, deeper tanks
Pump: D42A/B submersible with 20m lead | Flow @ 200 kPa: 40 lpm | Output: 0.60 kW
Same as KRBS1 with a 20-metre pump lead for tanks where a standard lead length is insufficient.

KRBS2 — for double storey homes
Pump: D53A/B submersible | Flow @ 200 kPa: 63 lpm | Output: 0.84 kW
Higher flow and pressure for double storey homes and larger simultaneous demand.

KRBS2/20 — for double storey homes, deeper tanks
Pump: D53A/B submersible with 20m lead | Flow @ 200 kPa: 63 lpm | Output: 0.84 kW
Same as KRBS2 with a 20-metre pump lead for deeper tank installations.

Not sure which model suits your home? Get in touch and we'll help you choose.

Why Kiwi homeowners choose the Davey RainBank submersible kit

• Pump is housed inside the tank — quieter running than a surface-mounted pump
• Pump cannot be tampered with by children or pets
• Rainwater used first automatically — no manual switching
• Seamless mains backup — no interruption when the tank runs dry
• Mains water flows through even during a power outage
• Built-in dual check valve — backflow protection included, not an add-on
• No solenoid valves — fewer moving parts, greater reliability
• Cleaner installation — no external pump housing required
• 20m lead options available for deeper tanks
• WaterMark certified and Smart Approved WaterMark
• 3-year guarantee backed by Davey's NZ dealer network

Operating limits

What's in the box

• KRBSA1: RainBank/S controller + D23A/B submersible pump with float + installation documentation
• KRBS1: RainBank/S controller + D42A/B submersible pump with float + installation documentation
• KRBS1/20: RainBank/S controller + D42A/B submersible pump with float (20m lead) + installation documentation
• KRBS2: RainBank/S controller + D53A/B submersible pump with float + installation documentation
• KRBS2/20: RainBank/S controller + D53A/B submersible pump with float (20m lead) + installation documentation

FAQ

Why choose a submersible kit over a surface-mounted kit?

The submersible pump sits inside the tank — quieter running, no external pump to house, and the pump cannot be accessed by children or pets. The trade-off is that the pump is less accessible for servicing. Surface-mounted kits are easier to access and maintain but require a protected external location.

What does the float switch do on a submersible kit?

The float is integral to the submersible pump and sits inside the tank. When the water level drops below the float, it signals the RainBank controller to stop the pump and switch to mains. This prevents the pump from running dry.

When do I need the 20m lead option?

If your tank is deep, or the controller is located a significant distance from the pump inside the tank, the 20m lead option (KRBS1/20 or KRBS2/20) provides the additional cable length needed. The standard KRBS1 and KRBS2 models include a standard lead length.

What happens when the tank runs empty?

Mains water flows through the RainBank to your outlets — the pump does not run. When rainwater returns, the system automatically reverts to rainwater priority.

What happens during a power outage?

Mains water continues to flow through the RainBank passively — no pump or controller power needed.

Does it protect against backflow?

Yes — a dual check valve is built into the controller, meeting the backflow protection requirements of AS/NZS 3500-1.

Does it need a plumber to install?

Yes — must be installed by a licensed plumber. This is a requirement of the WaterMark certification.

What warranty applies?

3-year guarantee backed by Davey's NZ dealer network.