Discontinued Product, please contact 0800 RINNAI for more information

Discontinued Product, please contact 0800 RINNAI for more information

HJ Cooper Stainless Steel Mains Pressure Hot Water Cylinders

HJ Cooper Stainless Steel Mains Pressure Hot Water Cylinders

** superseded by Rinnai Mains Pressure Stainless Steel cylinders**

Peace of mind

This range of mains pressure electric hot water cylinders comes with a 20 year limited warranty on the inner cylinder*. You won't find a longer warranty on any other electric hot water cylinder in New Zealand! Whats more, it's backed by Rinnai after sales support.

Energy efficient
• Curved element design ensures 98% of water is heated.
• Cold water inlet dip tubes deliver water to the bottom of the tank to avoid mixing of water
• No cylinder wraps required, all HJ Cooper cylinders meet NZ MEPS

MEPS = Minimum Energy Performance Standard
Future proof your home
Connect to a hot water heat pump or solar system with the extra eco inlet connection**, either now or in the future.

Install as a low pressure system then connect, without replacing your cylinder, to the luxury of mains pressure when you are ready.

• Lightweight, stainless steel makes transport and installation are a breeze
• Low maintenance, no sacrificial anode to maintain
• Future proofed, auto reset thermostat option means these cylinders can be solar and hot water heat pump ready

Innovative design
The 250 and 300 L cylinders have the option of a second element making recovery times quicker and making it less likely you'll run out of hot water.

* Please see the owner and installer guide, in the 'Technical' tab, for full warranty details
** Excludes 135 L cylinder

Suitable for:
• Indoor installations
• Mains and low pressure systems
• Domestic and commercial water heating applications
• Left or right hand plumbing connections
• Connection to open loop solar or hot water heat pump systems

Not suitable as a pool or spa heater.

Water quality
HJ Cooper water heaters are manufactured to suit most New Zealand council water supplies. However some water supplies can have a detrimental effect on the water heater, its operation and life expectancy.

Water supplies with a high level of calcium carbonate (hard water) can cause scaling on hot surfaces. We recommend a water temperature of no more than 65 °C to minimise scale build-up. Scale reducing or water softening devices should be considered in hard water areas. The unit is not guaranteed against damage due to scaling. 

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.
• 135 L: 2 or 3 kW
• 180 L: 2 or 3 kW
• 250 L: 2 or 3 kW*
• 300 L: 2 or 3 kW*
* Twin element options available
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 32 mins (2 kW), 2 hrs 22 mins (3 kW)

180 L

4 hrs 44 mins (2 kW), 3 hrs 9 mins (3 kW)

250 L

6 hrs 34 mins (2 kW), 4 hrs 23 mins (3 kW)

3 hrs 17 mins (2 x 2 kW), 2 hrs 11 mins (2 x 3 kW)

300 L

7 hrs 53 mins (2 kW), 5 hrs 15 mins (3 kW)

3 hrs 56 mins (2 x 2 kW), 2 hrs 39 mins (2 x 3 kW)


late 2017, superseded by Rinnai Mains Pressure Stainless Steel cylinders

Models and capacities table
  A (mm) B (mm) C (mm) D (mm) E (mm) Height (mm) Diam. (mm)
135 L 310 N/A 325 N/A 690 1023 ø 550
180 L 310 460 325 N/A 970 1295 ø 550
250 L 310 460 325 1080 1410 1730 ø 550
300 L 310 460 325 1380 1725 2047 ø 550

Ducted Gas Heating Service Centre

Ducted Gas Heating Service Centre
Operating 5 days a week, 8am to 5pm, Monday to Friday our New Zealand based customer service centre provides nothing but top quality. If you need to book in a Ducted Gas Heating service, we have a team of providers fully trained and equipped with diagnostic tools to service your appliance when you need them. 

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