Hybrids appeal where a full heat pump is hard to do right now: a newer boiler with years of life left, a large or draughty house where a full system would need a very large unit and many radiator changes, or a combi home with no cylinder space, as some hybrids keep the combi for hot water. They can also be a step towards a full system later.
In Hertfordshire, the outdoor unit of a hybrid needs the same airflow and siting care as any heat pump. Installers covering Hertfordshire set up the hybrid controller so you can see and adjust when each heat source runs. Combi homes in Hertfordshire with no space for a cylinder can look at a hybrid that keeps the combi for hot water.
Who it suits
- Combi homes with no room for a cylinder
- Homes with a fairly new boiler the owner wants to keep using
- Large or hard-to-insulate homes where a full heat pump is difficult for now
- Owners who want a stepping stone towards a full heat pump later
Grants and rules for heat pumps in England
Homes in Hertfordshire can use the Boiler Upgrade Scheme, which takes £7,500 off the cost of an air source heat pump when it replaces fossil-fuel or electric heating. Replacing oil or LPG heating qualifies for £9,000 for installations from 21 July 2026 to 31 March 2027, and air-to-air systems for £2,500. The MCS-certified installer named in your quote applies for the grant and deducts it from the price.
There is no VAT on installing a heat pump anywhere in the UK until 31 March 2027. In England most houses can have an air source heat pump under permitted development, provided the unit meets the MCS noise and siting standards; the old 1 m boundary limit was removed on 29 May 2025. We flag listed buildings, flats and sensitive conservation-area positions at survey.
Hybrid heat pumps prices in Hertfordshire
Here are typical prices for hybrid heat pumps in Hertfordshire, installed and including VAT. Use the guide price tool for a figure based on your home, then a survey confirms it in writing.
| System | Installed guide price |
|---|---|
| Hybrid heat pump alongside an existing boiler | £7,350–£11,550 |
Installed, inc VAT. Hybrid systems are not eligible for the Boiler Upgrade Scheme.
Towns we cover in Hertfordshire
We cover 17 towns in Hertfordshire for hybrid heat pumps. Each links to local guide prices and the grant position for England.
| Town | Postcode district | Nearest town | Midwinter daylight |
|---|---|---|---|
| Hemel Hempstead | HP2 | Berkhamsted | 7 h 47 min |
| Stevenage | SG1 | Hitchin | 7 h 45 min |
| St Albans | AL1 | Radlett | 7 h 47 min |
| Welwyn Garden City | AL8 | Hatfield | 7 h 46 min |
| Cheshunt | EN8 | Hoddesdon | 7 h 47 min |
| Hatfield | AL10 | Welwyn Garden City | 7 h 47 min |
| Bishop's Stortford | CM23 | Ware | 7 h 46 min |
| Hitchin | SG6 | Letchworth Garden City | 7 h 45 min |
| Hoddesdon | EN11 | Ware | 7 h 47 min |
| Letchworth Garden City | SG6 | Hitchin | 7 h 45 min |
| Harpenden | AL5 | St Albans | 7 h 46 min |
| Hertford | SG13 | Ware | 7 h 47 min |
| Berkhamsted | HP4 | Tring | 7 h 47 min |
| Ware | SG12 | Hertford | 7 h 46 min |
| Royston | SG7 | Letchworth Garden City | 7 h 44 min |
| Radlett | WD7 | St Albans | 7 h 48 min |
| Tring | HP23 | Berkhamsted | 7 h 47 min |
Hybrid heat pumps questions
Does a hybrid switch between heat sources automatically?
Yes. The hybrid controller follows rules set at commissioning: it might switch to the boiler below a chosen outdoor temperature, compare running costs using the prices you enter, or prioritise lower carbon. Some systems run both together in very cold weather. The installer sets these for your home and shows you how to adjust them when tariffs change.
Will a hybrid heat pump lower my bills?
It can reduce how much gas, LPG or oil you burn, but the effect depends on how the controller is set, your insulation, your tariff and fuel prices. You keep a boiler to service and, on mains gas, the standing charge. We do not promise a figure; instead the survey gives an estimate for your home comparing a hybrid with a full heat pump.
Is a hybrid a good step towards a full heat pump?
It can be, if the outdoor unit and pipework are sized with a future full system in mind. Later, once insulation has improved or radiators have been upgraded, the boiler can be removed and the system converted, provided the heat pump is large enough for the full load. Raise this at survey so the design leaves room to change.
Can a hybrid work with my combi boiler?
Yes, some hybrids are designed to work with a combi, with the heat pump heating the radiators and the combi continuing to provide hot water on demand. That avoids finding space for a cylinder, which is one of the main reasons people choose a hybrid. Other hybrid designs use a cylinder heated by the heat pump, with the boiler as backup.

