The Rinnai Home - Zen Plus domestic boiler and temperature accurate water heating system has been proven to be one of the most energy efficient home heating systems available today.

Rinnai UK have worked in conjunction with AECOM one of the UKs and world’s largest building consultancy firms on this ground breaking project. AECOM are leading experts in energy assessments, lifecycle cost analysis and building consultancy.

Why the Zen Plus System

As well as the host of benefits above the study compares the life cycle performance of heating systems available for a typical large family-sized home in the UK. Specifically the three configurations of natural gas boilers as well as an air-to-water heat pump configuration below.

  • System boiler supplying space heating and DHW via a cylinder
  • Combination boiler system serving both DHW and space heating
  • Dual boiler arrangement, with a dedicated water heater and a separate boiler for space heating
  • Air-to-water heat pump supply space heating and DHW via a cylinder

Life Cycle Costing Analysis 

This looks at overall costs over the service life of the heating system.

  • Initial capital costs,
  • Operational and maintenance costs.

The life cycle comparison was carried out over a period of 20 years based on the expected system service life prior to any replacement.

The NPV calculation is based on a discount rate of 3.5% (The GREEN BOOK - HM Treasury) and an inflation rate of 2% for servicing costs.

The Results  

Over the lifecycle of the appliances the results show that the Rinnai ZEN plus system as well as providing huge benefits over the other competing system is also the most cost effective to run over a 20 year period.

The commonly used boiler and storage vessel system is 12.5% more expensive, whilst the standalone boiler is 1.3% more expensive and the air to water heat pump is 55.2% more expensive.


For more information on this report and details on how AECOM and Rinnai have modelled these results contact us today and one of our advisors will be in touch to discuss. 

Take a shower not a bath

The energy saving trust believe that if everyone in a family of four swapped one bath a week for a five minute shower, it could save up to £20 a year on their gas bill. They also found that if a person spent 1 minute less per shower, then you could save an additional £7 per person every year. Look at changing your shower head to an eco-version too and additional saving will be made. The Rinnai Zen Plus system only uses water heat energy when you need it and as the Rinnai system heats the water instantly even greater savings can be made.


Take control of your heating

Use the Rinnai ME controller and app to monitor and alter your temperature whenever you’re at or away from home – with the ME controller you are always in control.

Are you heating rooms that aren’t being used? Make sure all your radiators have thermostats on them – and use them. The Energy Saving Trust suggests that turning down your thermostat by just one degree could save around £75 per year. 

Also, check whether heat could be leaving your home through gaps. Thick curtains, draught excluders, even a piece of putty in a small gap around a window will help keep the heat in.


Monitor your energy use

The Rinnai ME controller has a built in energy monitor to enable you to monitor precisely what energy you use for heating and hot water.

Also energy suppliers are in the middle of a smart meter rollout, with the goal of offering one to every home in England, Scotland and Wales by 2020. A smart meter shows you how much energy you’re using in pounds and pence. Smart thermostats like the Rinnai ME controller give you maximum flexibility when it comes to managing your heating. You can even control your heating when you’re out, using your smartphone, tablet or laptop.

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