Rinnai MS30055030 – MP300SS 550×2045 3kW

Product Details: Rinnai MS30055030

Rinnai MS30055030 – MP300SS 550×2045 3kW, part of the Stainless Steel Mains Pressure Indoor Cylinders range. Easy to install, and able to be connected to solar or heat pump installations, they are our premium hot water cylinder Genuine Rinnai New Zealand product, brand new, supplied through Rinnai NZ’s trade channel.

Rinnai MS30055030 — Specifications

Product Overview
Product	MP300SS 550×2045 3kW
Rinnai Part Number	MS30055030
Product Range	Stainless Steel Mains Pressure Indoor Cylinders
Category	Hot Water Systems > Water Heating > Standard
Brand	Rinnai
Technical Specifications
Diameter	550 mm
Anode	Not required
Connections	Hot and cold water connections ¾ ” (20 mm)
Construction	Inner cylinder: High grade duplex stainless steel; Outer casing: Galvanised steel
Element	Incoloy 825 alloy sheath element positioned at the bottom of the tank.
Maximum working pressure	850 kPa
Pressure testing	To 15 bar
Thermal insulation	CFC-free polyurethane foam, compliant with MEPS standard
Thermostat	Robert Shaw 30 A contact thermostat, manually resettable at 85 °C. Thermostat can be upgraded to an auto-reset thermostat for solar and hot water heat pump applications.
TPR valve	Rating of TPR supplied with cylinder— factory set to 850 kPa and 90 °C.
Weight empty (approx.)	135 L = 29 kg; 180 L = 35 kg; 250 L = 45 kg; 300 L = 53 kg
Cylinder recovery times (theoretical)	Based on a thermostat temp. setting of 60 °C and an incoming water temp. of 15 °C.; 135 L = 3 hrs 56 mins (2 kW), 2 hrs 37 mins (3 kW); 180 L = 5 hrs 15 mins (2 kW), 3 hrs 30 mins (3 kW); 250 L = 7 hrs 17 mins (2 kW), 4 hrs 51 mins (3 kW); 250 L = 3 hrs 39 mins (2 x 2 kW), 2 hrs 25 mins (2 x 3 kW); 300 L = 8 hrs 45 mins (2 kW), 5 hrs 50 mins (3 kW); 300 L = 4 hrs 22 mins (2 x 2 kW), 2 hrs 55 mins (2 x 3 kW)
Compliance	No cylinder wrap required. All Rinnai cylinders meet the NZ Minimum Energy Performance Standard (MEPS).
Market release	Late 2017
Order codes – standard lower element MRT thermostat	MS13555020 135 L 2 kW (diam. 550 mm, height 1020 mm); MS13555030 135 L 3 kW (diam. 550 mm, height 1020 mm); MS18055020 180 L 2 kW (diam. 550 mm, height 1295 mm); MS18055030 180 L 3 kW (diam. 550 mm, height 1295 mm); MS25055020 250 L 2 kW (diam. 550 mm, height 1730 mm); MS25055030 250 L 3 kW (diam. 550 mm, height 1730 mm); MS30055020 300 L 2 kW (diam. 550 mm, height 2045 mm); MS30055030 300 L 3 kW (diam. 550 mm, height 2045 mm)
Order codes – standard dual element MRT thermostat	MS250550; D; 20 250 L 2 x 2 kW (diam. 550 mm, height 1730 mm); MS250550; D; 30 250 L 2 x 3 kW (diam. 550 mm, height 1730 mm); MS300550; D; 20 300 L 2 x 2 kW (diam. 550 mm, height 2045 mm); MS300550; D; 30 300 L 2 x 3 kW (diam. 550 mm, height 2045 mm)
Order codes – standard upper element MRT thermostat	MS250550; U; 20 250 L 2 kW (diam. 550 mm, height 1730 mm); MS250550; U; 30 250 L 3 kW (diam. 550 mm, height 1730 mm); MS300550; U; 20 300 L 2 kW (diam. 550 mm, height 2045 mm); MS300550; U; 30 300 L 3 kW (diam. 550 mm, height 2045 mm)
Order codes – solar lower element ART thermostat	MS18055020; A; 180 L 2 kW (diam. 550 mm, height 1295 mm); MS18055030; A; 180 L 3 kW (diam. 550 mm, height 1295 mm); MS25055020; A; 250 L 2 kW (diam. 550 mm, height 1730 mm); MS25055030; A; 250 L 3 kW (diam. 550 mm, height 1730 mm); MS30055020; A; 300 L 2 kW (diam. 550 mm, height 2045 mm); MS30055030; A; 300 L 3 kW (diam. 550 mm, height 2045 mm)
Order codes – solar dual element ART thermostat	MS250550; D; 20; A; 250 L 2 x 2 kW (diam. 550 mm, height 1730 mm); MS250550; D; 30; A; 250 L 2 x 3 kW (diam. 550 mm, height 1730 mm); MS300550; D; 20; A; 300 L 2 x 2 kW (diam. 550 mm, height 2045 mm); MS300550; D; 30; A; 300 L 2 x 3 kW (diam. 550 mm, height 2045 mm)
Order codes – solar upper element ART thermostat	MS250550; U; 20; A; 250 L 2 kW (diam. 550 mm, height 1730 mm); MS250550; U; 30; A; 250 L 3 kW (diam. 550 mm, height 1730 mm); MS300550; U; 20; A; 300 L 2 kW (diam. 550 mm, height 2045 mm); MS300550; U; 30; A; 300 L 3 kW (diam. 550 mm, height 2045 mm)

Documents & Downloads

• 📄 Water Heating Catalogue
• 📄 Electric & gas hot water pocket guide
• 📄 Solar PV Solutions
• 📄 Mains pressure stainless steel owner & installer guide
• 📄 Mains pressure stainless steel product technical statement
• 📄 Stainless steel cylinders: Certificate of conformity (ESV)
• 📄 Stainless steel cylinders spares list
• 📄 Certificate of Compliance for NSF/ANSI 372-2022 Standard (Drinking Water System Components Lead Content)
• 📄 Stainless steel warranty
• 📄 CAD (AutoCAD DWG)

✔ Full Rinnai NZ Manufacturer Warranty — genuine Rinnai New Zealand product. Warranty & after-sales support.

Every Rinnai product sold by NZ Depot is brand new and dispatched NZ-wide. Order online today or contact NZ Depot for trade pricing and availability.

Need advice or trade pricing? Contact NZ Depot or browse more hot water, heating and HVAC deals at NZ Depot.

Pro Tip: Ensure this MS30055030 matches your installation. Sourced directly from the Rinnai NZ supply chain for full compatibility and manufacturer warranty.

Looking for the best price on the Rinnai MS30055030? NZ Depot supplies the Rinnai MS30055030 New Zealand wide with fast dispatch, trade pricing and genuine Rinnai warranty support. Compare the Rinnai MS30055030 – MP300SS 550×2045 3kW with the rest of the Rinnai Stainless Steel Mains Pressure Indoor Cylinders range, check the full specifications above, and order the Rinnai MS30055030 online today or request a trade quote for volume supply.

Browse the full range of Hot Water Systems available for NZ-wide trade and retail supply.

© 2026 NZ Depot Limited. All Rights Reserved. | 100% NZ Owned and Operated. | Authorised Rinnai Trade Supplier.