A Domestic Heat Pump: A Year in Review

The application process

The prerequisites then were a fully refundable (until the day before the installation) advance payment of £200 and a recent EPC (under 10 years) with no outstanding recommendations for cavity wall insulation. Our house is a three-bedroom semi, built as part of a council estate in Hove around 1950.

Regardless of the peace of mind that we wouldn’t have issues with the application, we did understand how important reducing heat loss is in an old home when you want to supply heat with an all-electric system. Electricity is still expensive and crucially we wanted to be sure this solution would work well and efficiently. We had done a lot of work in the house to improve efficiency: loft retrofit insulation, ground floor retrofit insulation with the opportunity of a ground floor extension, new double-glazed windows, and a new entrance door.

Once our application was submitted, we were booked in for a home survey about three weeks later. The home survey was meant to confirm the property’s eligibility for a heat pump and collect all the necessary information to run a heat loss calculation. The surveyor looked at every room, the loft and the outside, taking some measurements and making notes of materials and evidence of insulation. They took note of our boiler details, reviewed pipework and measured radiators.

Installation process and fine tuning

The installation took three days in early January 2025, and the pump has been running smoothly and keeping us warm without issues for just over a year now.

The first thing I noticed was how uniform the temperature felt throughout the house and throughout the day. With our boiler, in an effort to be as efficient as possible, we were running an almost militant schedule of operation with different running hours and setpoints per room depending on our schedule. With the heat pump running constantly all spaces feel equally comfortable 24/7.

A common concern around heat pumps is how noisy they can be. Although our external unit is on the wall on a path shared with our next-door neighbours, they have happily declared that they never hear it. Perhaps our context is idea, or perhaps domestic heat pump technology has managed to deliver practically quiet equipment, but it was definitely a happy myth buster for us.

We have optimised the heating for domestic hot water, as well as the weekly high temperature legionella cycle to match the times of day when our tariff is lowest.

The original set up of the heat pump was controlled by our existing smart meter based on the thermostat. We experimented with different settings and features and found that the weather department is the most efficient. This reads the outside temperature from sensors on the heat pump and adjusts the flow temperature in the system to ensure a stable internal temperature.

Energy consumption for heating and hot water

Looking at our last year of gas heating and our first year of the heat pump, our energy consumption over 2025 has been a fraction of that of 2024, with a 32% reduction on average. Although this is just an indicative comparison as the weather conditions of different years will impact a system’s performance, the drop in energy consumption during the heating season is impressive.

With the electricity prices remaining high and further increasing, this ambitious downward trend is unfortunately not reflected in the cost comparison. Our first year with the heat pump cost us about £100 more than the year before (approximately 7% increase). The energy landscape is continually changing, and it isn’t easy to predict future trends. Perhaps the only way to control this right now is through on-site energy generation and a lesser reliance on the grid as a result.