Installing a heat pump is a big step. But before you choose, you need to decide which type fits your home: a hybrid heat pump that works with your boiler, or an all-electric heat pump that fully replaces the boiler. This article lays out all the differences — so you make a well-informed choice.
What is a hybrid heat pump?
A hybrid heat pump is an air-to-water heat pump that sits alongside your existing boiler. The system automatically picks the most efficient heat source: at mild temperatures the heat pump runs, in severe frost the boiler kicks in. For hot tap water (shower, kitchen) the boiler remains responsible.
What is an all-electric heat pump?
An all-electric heat pump fully replaces your gas boiler. The system handles heating, hot tap water (via a 150–200 L buffer tank) and often summer cooling as well. The gas connection can be removed, which also saves on the standing charge (€200–€300 per year).
The full comparison
| Aspect | Hybrid | All-electric |
|---|---|---|
| Gas use | 40–50% of original | 0% (gas-free) |
| Gross investment | From €5,200 | From €9,500 |
| ISDE subsidy | €2,125 – €3,025 | €2,575 – €3,025 |
| Net investment | From €3,075 | From €6,925 |
| Payback period | ~5–7 years | ~9–11 years |
| Required insulation | Label C or better | Label B or better |
| Heating system | Existing radiators | Underfloor / LT radiators |
| Hot tap water | Via gas boiler | Via heat pump + buffer |
When to choose hybrid?
A hybrid heat pump is ideal if:
- You live in a home with energy label C, D or E.
- You don't want to replace your entire heating system.
- You have a relatively young gas boiler that still works well.
- Your budget is limited — a hybrid is much cheaper to buy.
- You live in a terraced or semi-detached home with radiators.
Tip: hybrid is also an excellent first step. Improve your insulation later and then replace your gas boiler with hot tap water via the heat pump.
When to choose all-electric?
All-electric is the right choice if:
- Your home has at least label B (HR++ glass, insulated cavity walls).
- You have underfloor heating or are willing to install LT radiators.
- You want to fully get off gas (and save the standing charge).
- You think long-term — a 9–11 year payback fits your plans.
- You also value summer cooling.
Example: annual costs
For an average terraced home (1,000 m³ gas + 3,000 kWh electricity per year):
| Scenario | Energy cost/year | Saving/year |
|---|---|---|
| Gas only | €1,500 + €750 = €2,250 | — |
| Hybrid heat pump | €700 (gas) + €1,000 (electricity) = €1,700 | €550 |
| All-electric heat pump | €0 (gas) + €1,300 (electricity) = €1,300 | €950 |
What if I don't have underfloor heating?
For all-electric the system runs best at low flow temperatures (30–40°C). Have standard high-temperature radiators? Three options:
- Replace with LT radiators (low temperature) — costs €1,500–€3,000.
- Install underfloor heating — costs €3,000–€8,000 but gives optimal comfort.
- Choose hybrid — your existing radiators continue to work fine.
Conclusion
The choice depends on your insulation, budget and willingness to work on the heating system. Hybrid pays back faster and fits almost any existing home. All-electric is more sustainable but requires good insulation and (often) underfloor heating.
Still undecided? Schedule a free home check. Our installer reviews your insulation, central heating and usage habits and gives honest advice — no sales pitch.
More details on our deep-dive pages: hybrid heat pump and all-electric heat pump.