If your boiler is on its way out, you’re facing a decision that didn’t really exist ten years ago: replace like-for-like, or switch to a heat pump? Both camps have loud advocates, and most of what’s written is trying to sell you one or the other.
We install both, so we don’t have a horse in this race — the right answer genuinely depends on your home, your current fuel, and how long you’re planning to stay. Here’s the honest comparison.
The Short Version
A new boiler wins on: upfront cost, familiarity, and drop-in simplicity — it slots into the system you already have.
A heat pump wins on: running efficiency, lifespan, ditching fossil fuels, and — right now — a government grant that dramatically closes the price gap.
The deciding factors are usually: what fuel you’re on today, how well your home holds heat, and whether your radiators and cylinder suit lower-temperature running.
Upfront Cost — Closer Than You’d Think
A straight boiler swap is the cheaper ticket, no argument. But the gap has narrowed hard: the Boiler Upgrade Scheme takes £7,500 off an air source or ground source heat pump , rising to £9,000 for oil and LPG homes between July 2026 and March 2027 — and heat pump installations carry zero VAT. Once the grant’s deducted (your installer does this off the quote — you never handle it), a heat pump often lands closer to a premium boiler installation than people expect.
What adds cost on the heat pump side: some homes need radiator upgrades or a new hot water cylinder to run well at lower temperatures. A proper survey tells you this before you commit — beware anyone quoting without one.
Running Costs — It Depends What You’re Burning Now
Here’s the honest mechanics. Electricity costs several times more than mains gas per unit — but a well-designed heat pump produces three to four units of heat for every unit of electricity it uses, where a boiler produces less than one. Those two facts roughly offset, which is why well-installed heat pumps typically run at similar or somewhat lower cost than a gas boiler — and why design quality matters more than the appliance : a poorly specified heat pump runs expensively, a well-specified one doesn’t.
If you’re on oil or LPG, the maths shifts decisively. You’re not comparing against cheap mains gas anymore — and combined with the £9,000 grant window, off-grid homes are where heat pumps make their strongest financial case. Around the villages here, that’s a lot of houses.
Comfort — Different, Not Worse
Boilers blast heat fast and switch off. Heat pumps run longer, gentler and lower — steady warmth rather than peaks and troughs. Most people who switch end up preferring it, but it’s a different rhythm: the house sits at temperature rather than heating up on demand. Heat pumps pair especially well with underfloor heating , which loves exactly those low, steady temperatures — it’s why we so often install the two together.
Lifespan and Maintenance
A modern boiler typically gives you 10–15 years; heat pumps are generally expected to run 15–20+, with fewer moving parts doing violent things. Both want an annual service. Over the appliance’s life, the heat pump usually needs replacing once where boilers need it twice — worth weighing in any long-term comparison.
When a New Boiler Is the Right Call
We’re Gas Safe registered boiler installers, and we’ll say it plainly: sometimes the boiler is the right answer.
You’re moving within a few years — you may not be there long enough for the efficiency gains to matter. Budget is tight right now — a reliable new boiler beats limping another winter on a dying one. Your home genuinely doesn’t suit one yet — poorly insulated properties or homes with no space for an outdoor unit or cylinder may need other work first. A good installer tells you this at the survey rather than selling you the wrong system.
When a Heat Pump Is the Right Call
You’re on oil or LPG — strongest case, biggest grant, best comparison. You’re renovating anyway — if walls are open and floors are up, it’s the perfect moment to design the system properly (and add underfloor heating while you’re at it). You’re staying put — long-term owners collect the full benefit of lower running costs and longer lifespan. Your boiler is dying and you want to decide once — replacing a boiler now likely means burning gas until the 2040s; some people would rather make the switch while the grant exists.
Frequently Asked Questions
1. Do heat pumps work in winter?
Yes — they’re standard heating in Scandinavia, which gets rather colder than Essex. Output is designed around your home’s heat loss, which is what the survey calculates.
2. Do I need to replace all my radiators?
Sometimes some, rarely all. Radiators sized for high-temperature boiler water may need upsizing to work at heat pump temperatures — the survey identifies exactly which, before you commit to anything.
3. Can I keep my combi setup with no cylinder?
Heat pumps need a hot water cylinder, which is genuinely a constraint for some smaller homes. If space is impossible, that’s a factor towards the boiler column — and worth an honest conversation at survey.
4. Is the grant really deducted upfront?
Yes — the installer claims it and takes it off your quote. You never apply for anything or wait for money back.
Get an Honest Answer for Your Home
We install boilers, heat pumps and underfloor heating across Essex and Suffolk — so our only interest is recommending the system that actually suits your house. Tell us what you’ve got and what you’re weighing up, and we’ll give you a straight answer and a free quote.
Planning a project? See our plumbing & heating in Essex service, our boiler installation cost guide and Boiler Upgrade Scheme guide, or get a free quote.
