The Full Installation Service

Octopus provides a complete installation service, handling everything from the initial quote and survey to supply, removal of old equipment, installation, commissioning and aftercare support. If, like me, you’re looking for a turnkey solution, this comes as close as I’ve found.

However, it’s not yet a commercial off-the-shelf (COTS) product. Having gone through the conversion from a gravity-fed water system to mains supply, I found this was a bigger deal than expected. The pump itself has been great, and I highly recommend ASHPs.

Here’s my take on how things went with this new technology and bespoke installation.

The Quote

In May 2024, I saw an Octopus campaign on Facebook offering a “quick quote” for heat pumps and solar. I clicked through and received a quote almost instantly.

The following week, I had a pre-sales call with Octopus to go over details. The process involved a £500 fully refundable deposit (which is now down to £200) to get a heat loss survey. I decided to go for it. My 24-year-old 3kW Ideal system boiler was showing its age. Since I was planning a kitchen refurbishment and considering moving to a combi boiler in the airing cupboard, this seemed a more long-term option. Gas will be phased out in the next 25 years, so I didn’t want to be stuck with an obsolete gas boiler.

Though the wait time was expected to be up to three months, there was an opening the following week, so I booked it.

Why I Chose Octopus

I wouldn’t say I’m an Octopus fan, but I am a convert. I checked out founder Greg Jackson and his values, which I found aligned with my own. Having worked in high-tech and multi-billion-pound corporations all my life, I know all big companies have their downsides, but Octopus has been impressive. I’d been moved to Octopus from Bulb after they went bust. For anyone interested, there’s a great interview with Greg Jackson by Heat Geek, which gives insight into the company’s vision.

The Octopus service includes a pre- and post-contract insurance policy with HIES, electrical certification through NAPIT, and MCS certification, which grants access to the £7,500 Boiler Upgrade Scheme (BUS) via Ofgem. Given the horror stories of fly-by-night installers and local companies online, Octopus felt like a safe bet.

At this point, I broke from tradition and didn’t seek other quotes. I didn’t feel knowledgeable enough to make an informed choice, so, like picking wine by the label, I chose based on Octopus’s reputation.

The Survey

Not knowing much about heat pumps, I turned to the internet and came across Heat Geek, Renewable Heating Hub and Skill Builder on YouTube. It all seemed quite complex. I’m an engineer by trade and a project manager by occupation, so I’m comfortable with numbers. I even tried a few heat loss calculations through online radiator shops.

When the Octopus surveyor arrived, he spent about five hours on the survey. He went over radiator plans, room-by-room heat loss, the 50°C design flow temperature and cable routing. We also discussed the loft insulation, and placement of the ASHP and consumer unit. I felt reassured by the surveyor’s approach and the quality of his analysis.

The Results

Most of the discussion focused on my pipework. I live in a timber-framed, well-insulated 2000-built semi-detached home. Two years ago, I added 300mm of loft insulation. The old boiler was fitted with primary pipework that runs from the kitchen to the airing cupboard and loft, where there’s a header tank. The pipework is 10mm microbore, which Octopus allows as long as it’s barriered, which mine is.

After discussing the radiator plan, I signed the contract, and within a week, I had an install date for August – just two months away.

The Equipment

The heat loss survey was done with a design temperature of 22°C for bathrooms, 18°C for bedrooms and 21°C elsewhere, with an outside design temperature of -2.4°C. The survey showed a heat loss of 4.1kW. The surveyor recommended swapping six radiators, providing a total output of 4.6kW. Initially, Octopus specified a Daikin Altherma 4kW Monoblock with a 180L hot water cylinder. Later, I switched to the Cosy 6 and upgraded to a 250L cylinder, as recommended by MCS.

Pre-Installation Requirements

The only pre-installation task on my end was clearing a space for the pump in the garden. Octopus handled everything else, including a new EPC, BUS grant application and DNO approval for the electrical circuit. My EPC came back as a C rating, and the BUS grant was approved.

Cosy 6 Launched

After signing the contract, I was offered a swap to the Cosy 6, Octopus’s in-house unit. Given that the future of Octopus seemed to be in its own products, I decided to switch to the Cosy 6. I also upgraded to a 250L hot water cylinder to better meet my household’s needs.

Pre-install Setup

A week before installation, scaffolding went up so Octopus could run a cable from the new consumer unit through the loft to the ASHP. The scaffolding was up front and back, depending on where your installation needs it, and was taken down a few days after installation.

The Installation

Planned for five days, the installation took six. A team of plumbers and electricians arrived on day one with all the required equipment. The ASHP site was prepared with a hard-standing base instead of a soakaway. My pump’s site is close to the garage wall, making for a very short external pipe run.

Inside, Octopus installed the DHW cylinder, a 26L volumiser, a Fernox TF1 filter, ESBE diverter valve, expansion vessel and a by-pass valve. In the airing cupboard, they cleared out the old system, making it available for storage. Octopus also took care of all the installation waste.

Conclusions

The system was completed with thermostat and humidity sensors (one per zone; I have one zone with two sensors). The small, wireless sensors are discreet and functional. The Cosy Hub, which connects to Wi-Fi, was set up quickly and is straightforward to use. Though the app currently has basic functionality, the system defaults to weather compensation, which has kept our home warm.

In October and November, with outdoor temperatures around 7-11°C, the ASHP used 234.01kWh, delivering 964.32kWh of output with a SCOP of 4.12. The Cosy Tariff, with three off-peak slots daily, has also been beneficial.

Finally, I opted for the £9/month service plan (included free for the first year), covering annual maintenance.

The Octopus Cosy 6 ASHP – What is it?

The Octopus Cosy 6 Air Source Heat Pump (ASHP) runs on R290 (propane) refrigerant. This system has a 6kW output and is installed with a Cosy Hub controller, along with up to four thermostat and humidity sensors. For Octopus customers, it can be accessed in the Octopus App under “Devices.” Recently, Octopus also announced the Cosy 10, a 10kW version of the heat pump.