Superseded by the Rinnai Mains Pressure Stainless Steel cylinders.
Connect to a hot water heat pump or solar system with the extra eco inlet connection (excl. the 135 L).
Install as a low pressure system then connect, without replacing your cylinder, to the luxury of mains pressure when you are ready.
Convenience
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.
Suitable for
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.
| Model / code | Capacity | Element size |
| MS13555020 | 135 L | 2 kW |
| MS13555030 | 135 L | 3 kW |
| MS18055020 | 180 L | 2 kW |
| MS18055030 | 180 L | 3 kW |
| MS25055020 | 250 L | 2 kW |
| MS25055030 | 250 L | 3 kW |
| MS30055020 | 300 L | 2 kW |
| MS30055030 | 300 L | 3 kW |
Not required
Hot and cold water connections ¾ " (20 mm)
Inner cylinder- duplex stainless steel
Outer casing - galvanised steel
Incoloy 825 alloy sheath element positioned at the bottom on the tank. Twin element options are available.
850 kPa
To 15 bar
CFS-free polyurethane foam compliant with MEPS standard
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.
Rating of TPR supplied with cylinder—factory set to 850 kPa and 90 °C
Based on a thermostat temp. setting of 60 °C and an incoming water temp. of 15 °C
| Model | 2 kW | 3 kW | 2 x 2 kW | 2 x 3 kW |
| 135 L | 3 hrs 32 mins | 2 hrs 22 mins | - | - |
| 180 L | 4 hrs 44 mins | 3 hrs 9 mins | - | - |
| 250 L | 6 hrs 34 mins | 4 hrs 23 mins | 3 hrs 17 mins | 2 hrs 11 mins |
| 300 L | 7 hrs 53 mins | 5 hrs 15 mins | 3 hrs 56 mins | 2 hrs 39 mins |
Late 2017 and superseded by the Rinnai Mains Pressure Stainless Steel cylinders
If you’ve ever wondered why we call it a ‘Smart’ Cylinder, here’s what makes it so clever.
Read Article
If you’re not on mains water pressure yet, you really should be. Here are 5 good reasons to make the switch.
Read Article
What’s the best way to heat your water? Gas or electricity? Continuous flow or a storage cylinder? Low pressure or mains pressure? All your questions are answered here.
Our stylish and efficient heating and cooling solutions are designed to bring you total home comfort.
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