rinnai_hotflo_heat_pump

Product Review: Rinnai Hotflo Hot Water Heat Pump

Have you considered heating your water with a heat pump? Heat pump water heaters are becoming increasingly popular with home owners looking for more efficient methods of water heating.

How do they work and what are the benefits?
Heat pump water heaters work like fridges in reverse, using electricity to move heat from one place to another instead of generating the heat. They can be up to three times for efficient than a conventional electric hot water cylinder. To move the heat, heat pump water heaters pull heat from the surrounding air and dump it at higher temperature into a tank to heat the water.

rinnai_hotflo_heat_pumpTHE RINNAI HOTFLO HEAT PUMP WATER HEATER

The Rinnai Hotflo Hot Water Heat Pump was designed for homeowners who want to significantly reduce running costs while minimising their carbon footprint. Rinnai state that the Hotflo heat pumps offer an energy consumption profile similar to solar water heating systems and can generate up to 700 liters of hot water per day. Under normal operating conditions, the Hotflo will will around 66% electricity than a typical electric hot water cylinder.

Key benefits and features:

  • Retrofits to virtually any brand of electric hot water cylinder
  • Simple installation, usually takes less than one day
  • Carbon footprint reduction with reduced energy consumption

Specifications

Rated input 1.9 kW
Max. energy output 6.0 kW
This is the maximum possible from the unit and should be used to ensure the tank TPR valve is suitably sized.
Max. water pressure 850 kPa
Refrigerant type/mass R134A/750 g
Refrigerant pressure High 2.7 MPa, Low 1.0 MPa
Refrigerant compressor oil Type: Neo 32, quantity: 520 ml
Ingress protection IP24
Noise level Fan approx. 55 dB(A)
Net weight 60 kg
Power supply 240 V, 50 Hz

Ambient temperature operating range
Operating temperature range is -7 to 45 °C. When the ambient temperature is below 2 °C the tank temperature achieved may be lower. When the ambient temperature is high, the air supply fan will run at a lower speed.

Start up protection
When the power is first turned on to the heat pump, or when the power is cut, then retsored, the unit will not start for three minutes. This is to protect the condenser.

Defrosting function
The heat pump has protection systems that will stop the operation of the unit if; the air inlet/outlet is blocked, voltage is out of nominal range (207-255 V), over pressure, or over temperature in the refrigerant system.

CONS OF THIS PRODUCT

Despite being very efficient, the best heat pump units will be more costly than an electric water heater and are more likely to have failures than electric water heaters. Installation will also be trickier, as they need a supply of warm air to be able to run effectively. This can be a disadvantage during the winter and in colder places.

Indoor Installation
Installation indoors could be challenging due to how these heat pump systems work. Because the heat pump uses the air around it, and exhausts cold air, it will be increasing more difficult for it to extract heat from the same cold air it has extracted. This wastes power and extends the running time of the heat pump, making it less efficient. If using a split system, you will want to heat pump installed outside and the tank inside, which will work well.

Repair Costs
It is common to be facing repairs soon into the life of a heat pump system, usually once the warranty has expired.

Noise
Heat pumps do make a humming sound similar to an air conditioner while operating. This could cause disruption depending on placement and how sensitive to sound the occupants of the house are, so this should be taken into account when deciding where to install the unit.

CONCLUSION

Heat pump water heaters are a good option for high hot water users who want to improve the efficiency and performance of their water heating system. They provide a fast ROI, being up to three times more efficient than electric water heating systems. The Rinnai Hotflo Hot Water Heat Pump is a top of the range choice if you want to go the heat pump route, providing you with efficient water heating and hot water on standby.

For more information on the Rinnai Hotflo Heat Pump, download this PDF.
pdfRinnai Hotflo Heat Pump Water Heater PDF