Wetback is something that you mostly associate with an old house with a low pressure copper cylinder connected to an old wood burner. With a Rinnai thermosiphon cylinder you can now have a new modern house with mains pressure water heated by your wetback fire, saving you money on your power bill.
Thermosiphon coil for wetback
Water is circulated through a coil inside the cylinder by a thermosiphon effect, i.e. warmer water rises and cooler water falls, creating a natural flow. This means there is no need for a pump to circulate water, you can still heat your water even if there's a power cut.
Eco inlet
Added benefit of an eco inlet that allows connection to an open loop* (potable) solar system, or a hot water heat pump.
* For open loop solar systems the potable water (suitable for drinking and food preparation) from the cylinder flows through the collector—water that flows through the system is used directly by the household.
Suitable for:
- indoor installations only
- mains and low pressure systems
- connection to a wetback fire and/or an open loop solar system or hot water heat pump
- residential and light commercial water heating applications
No suitable as a pool or spa heater, or for underfloor heating.
Water quality
Rinnai cylinders are manufactured to suit most NZ council water supplies. However some supplies can have a detrimental effect on the cylinder, its operation and life expectancy. Stainless steel cylinders are not suitable for bore or tank water.
Single thermosiphon coil lower element
For new builds and renovations connecting to a wetback fire, where the homeowner will have full electric boost when there is not enough heat from the wetback fire. System can also be connected to an open loop solar or hot water heat pump.
Single thermosiphon coil dual element
For new builds and renovations connecting to a wetback fire, where the homeowner wants faster recovery times, and to reduce the risk of running out of hot water. Cylinder will have higher running costs. System can also be connected via the eco inlet to an open loop solar system or hot water heat pump.
Single thermosiphon coil upper element
For new builds and renovations connecting to a wetback fire, where the homeowner relies heavily on heat from the wetback and/or open loop solar system or hot water heat pump. Upper element is only used to quickly heat water in the top of the cylinder.
10 years
IPX1
supplied
All cylinders EXCEPT the 190 L are 560 mm diameter.
• 190 L 2 kW - MS190550CT20
• 190 L 3 kW - MS190550CT30
• 250 L 2 kW - MS250560CT20
• 250 L 3 kW - MS250560CT30
• 300 L 2 kW - MS300560CT20
• 300 L 3 kW - MS300560CT30
• 250 L 2 kW - MS250560CTU20
• 250 L 3 kW - MS250560CTU30
• 300 L 2 kW - MS300560CTU20
• 300 L 3 kW - MS300560CTU30
• 250 L 2 kW - MS250560CTD20
• 250 L 3 kW - MS250560CTD30
• 300 L 2 kW - MS300560CTD20
• 300 L 3 kW - MS300560CTD30
Inner, high grade duplex stainless steel
Outer, galvanised steel
CFC free polyurethane foam, compliant with NZ MEPS
• Wetback thermosiphon coil 1 " 25 mm diameter
• Length 10 m (0.785 m2)
• Maximum kW rating 13.4 kW
Incoloy 825 alloy sheath element, options; 2 kW, 3 kW, 2 x 2 kW, and 2 x 3 kW
Robert Shaw 30 A contact auto-reset (red dial)
TPR supplied, 850 kPa, 99 °C, 46 kW
| Model | Empty | Full |
| 190 L | 42 kg | 232 kg |
| 250 L | 48 kg | 298 kg |
| 300 L | 56 kg | 356 kg |
No cylinder wrap required. All Rinnai cylinders meet the NZ Minimum Energy Performance Standard (MEPS).
June 2022
• Thermostat Robert Shaw red dial (ART solar) - 30015
• Kawai element solar 2 kW 230 V - 30062
• Kawai element solar 3 kW 230 V - 30063
• TPR MP 850 kPa HT575 20 mm 99 °C, 46 kW - BE11004781
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