The National Residential Landlords Association (NRLA), a private landlord membership organisation, has officially partnered with Nesta's Money Saving Boiler Challenge, Nesta announced on 10 February 2023. The campaign encourages landlords to help tenants turn down the flow temperature on combi boilers1.
Nesta's research found that 53% of renters were not aware it was possible to change the flow temperature on a boiler, compared with 41% of homeowners. Nesta says this adds up to more than 2.5 million private rented households missing out on the tip, with combined potential annual household savings of around £100m for those homes with combi gas boilers1. Reducing flow temperature from 80 to 60 degrees can save households around £112 a year by enabling condensing boilers to run more efficiently1.
Polling after Nesta's awareness campaign showed that of those renters who had seen messages about the tip, 14% took no action because they were not sure their landlord would want them to change the boiler settings1. The private rented sector across the UK totals 5.4 million households based on the latest data from England and Wales, Scotland and Northern Ireland1.
Nesta commissioned Cambridge Architectural Research to estimate how many homes could save energy by turning down combi boiler flow temperatures. The figures are set out below.
| Measure | Figure |
|---|---|
| UK homes with gas combi boilers | 57% |
| UK homes able to meet heat demand on an average winter day at 60°C | 72% |
| UK homes that could benefit from turning flow temperatures down to 60°C | 38%, around 10.7m homes |
| Total saving on bills per year across those homes | £1bn |
Nesta notes that some homes may have already made the change, or may be using advanced boiler controls that adjust flow temperatures automatically1.
"Turning down the boiler flow setting to 60 degrees can save renters money without affecting the temperature in a house. This is one of several things that tenants looking to reduce the amount they spend on energy, and their carbon footprint, can try. The NRLA encourages landlords to work with their tenants to help reduce their energy bills."
The Money Saving Boiler Challenge was launched last year by Nesta and is run in partnership with Which?, Energy UK, EDF, E.ON Next, Octopus Energy, OVO Energy and Heating Hub. Over 200,000 people have used the online tool already, according to Nesta1.
Why it matters for households
For a household with a combi boiler, the boiler flow temperature setting determines how hot the water sent around the heating system is. Nesta's case is that lowering it from 80 to 60 degrees lets a condensing boiler run more efficiently, cutting gas use without changing the temperature a home reaches. The saving of around £112 a year is a reduction in running cost, not a change to the heating system itself, and Nesta says the action takes minutes and does not require removing the boiler front or using tools1.
For renters, the barrier is permission rather than cost. The finding that 14% of renters who saw the tip took no action because they were unsure their landlord would want the boiler settings changed points to a question of who controls the appliance. Guidance on asking a landlord for energy improvements and on what tenants can and cannot change covers where that boundary sits, while landlord duties on energy, heating and home safety set out the landlord's side. The NRLA's involvement matters because it puts a landlord body behind a change that tenants can make themselves, at no cost, on equipment the landlord owns.
The wider estimate is that around 10.7m UK homes could benefit, saving a total of £1bn on bills per year1. That figure covers owner occupiers as well as renters, so the household-level effect depends on the boiler type and controls already fitted.
What happens next
The NRLA partnership was announced in February 2023, with the association urging its members to help tenants. No further dated steps are set out in the announcement. The online tool to reduce boiler flow temperature is at www.moneysavingboilerchallenge.com1.