Hot tips to prep your heat pump for winter
Even when it’s freezing outside, heat pumps easily beat gas boilers on efficiency. Don't just take our word for it - check out what our customers think.
Naturally, when it’s freezing outside, any heating system has to work a bit harder to keep your house warm. This means you'll use more energy, but don't worry - we always factor this winter bump into your energy cost estimates.
Tweak your settings
Switch to a smart tariff: If you can be flexible with your energy, our Cosy Octopus tariff is designed to save you money by shifting your heat pump usage to cheaper, off-peak times.
Tweak your hot water: Set your hot water cylinder to 48°C. Pushing it much higher can trigger the booster ‘immersion’ heater, which just costs you more money to do the same job.
Set-back temperatures: Keep your heating on consistently, rather than letting the house go completely cold overnight. Set your overnight 'set-back' temperature just 2 degrees lower than your daytime ideal so your heat pump doesn't have to run a marathon to warm things back up the next morning. (Top tip: if you prefer a cooler bedroom, just turn down the individual radiator valve in that room!).
Got a Cosy? Check your Hush Mode: If your home isn't getting warm enough, check your app to make sure Hush Mode isn't activated. This feature limits compressor and fan speeds to 60%, which can make your heat pump struggle to hit target temperatures during the colder months.
Quick physical checks
Bleed your radiators: This removes trapped air that can stop heat from circulating properly. If a radiator feels cold at the top but warm at the bottom, air is usually the culprit. Read our step-by-step guide on how to bleeding radiators.
Top up your pressure: After bleeding radiators, or if you haven't used the heating for a while, the system pressure might drop. Use the mains filling loop to top it back up to between 1 and 1.5 bar cold. Read our guide to topping up system pressure.
Give it space: Ensure your outdoor unit has 1.5 meters of clear space in front of or above. Use a soft brush to clear away leaves and twigs, but never use a hose, pressure washer, or metal brush.
Seeing steam or hearing extra noise? Don't panic
On cold, damp days, your heat pump will run a quick 10-minute defrost cycle to melt ice, which can produce plumes of vapour outside or cause your radiators to cool down for a few minutes. Your unit may also seem louder in colder weather or during its hot water cycle. Both of these quirks are completely normal, fully automatic, and something you can blissfully ignore.
Want to know more about your heat pump?
Check out our full library of heat pump manuals to get to know your setup inside out.
Or check out our ultimate heat pump guide.
Something not quite right?
If something still doesn't seem quite right, or you just have a burning question, pop over to our heat pump support hub. You'll find extra troubleshooting guides and all the ways to get in touch with our expert team.
Cosy heat pump customers on the Cosy Octopus tariff saved an average of £205 last year compared to using a gas boiler running at 85% efficiency on our standard variable tariff
This figure is based on the actual energy consumption of all Cosy heat pump customers on a Cosy Octopus tariff between 1 Oct 2025 and 1 Oct 2026 , using tariff rates at the time.
We compared this to the cost of producing the same amount of heat with a gas boiler operating at 85% efficiency, priced using our Flexible Octopus (standard variable) tariff at the same time.
Savings from gas standing charges were included only for customers who had fully removed their gas supply (less than 2% of customers). Actual savings vary depending on system design, tariff choice, home insulation and energy use.
Our typical heat pump price is £4,064, which is lower than the national average of £5,408
This is the median post-survey price from all of our heat pump quotes after the £7,500 Boiler Upgrade Scheme has been applied, between 01/06/2026 and 30/09/2026. The national average is taken from the Boiler Upgrade Scheme statistics: April 2026 – median cost of installation Q3 2026.
Cut carbon emissions by 85% with a heat pump
This is the typical reduction in heating carbon emissions using an electric powered heat pump compared to a gas boiler.
The carbon breakdown
Gas CO2 (tonnes per year) - 2.00
Electricity CO2 (tonnes per year) - 0.31
Carbon saving (tonnes per year) - 1.69
Data sources and assumptions
Gas Energy Usage (kWh) 9500 (Ofgem medium use gas usage (Oct 2026))
Heat Pump Efficiency 312% (typical seasonal coefficient of performance from a fleet of Octopus high temperature heat pumps)
Gas Boiler Efficiency 85% (The typical gas boiler efficiency from a BEIS study)
Gas fuel emissions of (gCO2/kWh) 210 (SAP 10.3)
Electricity fuel emissions of (gCO2/kWh) 119 (SAP 10.3)
Based on these sources, heat pumps typically produce lower operational emissions when heating the home than gas boilers.
For more information, explore our Octopus Cosy heat pump fleet performance dashboard.
We're the largest heat pump installer on the Boiler Upgrade Scheme
Based on Octopus benchmarking against Ofgem reports from 2026, and we've continued to grow since.
Our customers love their heat pumps!
93% of people say it's the same or more comfortable than their previous boiler
87% say it costs the same to run or less
83% say it's the same noise or less than the previous boiler
90% say it's just as easy or easier to maintain
We survey all our heat pump customers 3 months post-installation to see how they find their heat pump compared to their previous gas boiler. Survey results are taken from a sample of 2,837 customers:
Comfort: 93% of people say it is the same or more comfortable than their previous boiler.
Running Costs: 87% say it costs the same to run or less.
Noise: 83% say it is the same noise or less than the previous boiler.
Maintenance: 90% say it is just as easy or easier to maintain.
A heat pump is around 4x more efficient than a gas boiler
Heat pumps don't generate heat by burning fuel. Instead, they transfer existing heat into your home. This means they can deliver multiple units of heat for each unit of electricity used.
Based on performance data from a fleet of installed Octopus Cosy heat pumps, typical real-world seasonal performance (SPF or SCOP) is around 3.6. This means around 3–4 kWh of heat is delivered for every 1 kWh of electricity used (an effective efficiency of 300–400%). By comparison, typical UK domestic gas boilers operate at around 85% efficiency, delivering approximately 0.85 kWh of heat per 1 kWh of gas used. On this basis, a heat pump can be around 4× more efficient than a typical gas boiler.
All our heat pumps are independently tested by the Building Research Establishment (BRE), with SCOP values published on the Microgeneration Certification Scheme (MCS) product database. Actual efficiency will vary depending on the property, system design, and usage. For more information, explore our Octopus Cosy heat pump fleet performance dashboard.
The UK's most awarded energy supplier
We've won more awards for customer service than anyone else.
Heat pumps give reliable, consistent heating and hot water
The heat pump user survey report by Nesta from May 2023 summarises that "users are highly satisfied with their heat pumps". It states: "People living in England, Scotland and Wales who own their home and use a heat pump to heat it are satisfied that heat pumps are safe, reliable, quiet heat sources that are effective for space heating and producing hot water." Find the full report here.
The Cosy heat pump is quiet
Heat pump sound power levels are verified by an independent, third-party laboratory as part of the testing process for inclusion on the MCS product database. The laboratory verifies the sound power on the A-weighted decibel curve, as A-weighting closely aligns to how humans perceive "loudness".
All heat pumps are measured using EN14511 standards to ensure uniformity across manufacturers and models. Our Cosy 6 heat pump has a verified sound power level lower than many other heat pumps of the same capacity.
Heat pump heating makes the air healthier in your home
Homes with a heat pump emit far less harmful nitrous oxide (NOx) emissions than those with gas boilers and cookers, significantly reducing asthma and other respiratory illnesses. According to the Sustainable Markets Initiative Cleantech Homes report.
A heat pump can add thousands to your property value
Analysis by the Department of Land Economy at the University of Cambridge suggests a 16% value uplift for new-build homes with enough solar and battery storage to eliminate energy bills. A further study of over five million existing properties indicates a 2-3% value increase for existing homes with solar panels or heat pumps (versus like-for-like gas-heated homes), according to the Sustainable Markets Initiative: Cleantech Homes report, 2024.
As of July 2026, the average house price in the UK is £272,611 according to the Land Registry. Therefore, a 2-3% value increase for an average house priced at £272,611 would be between £5,460 and £8,190.
Heat pumps typically last longer than gas boilers
The expected lifespan of a typical gas boiler is 10–15 years. A heat pump typically has a lifespan of 15–20 years, with UK government research indicating an average of around 20 years. Manufacturer Daikin reports similar ranges. Actual lifespan depends on factors such as installation quality, maintenance, usage patterns, and operating conditions.
Updated on
Becky Boulton
Green Hero
Published on 17th December 2022