A heat pump hot water cylinder is an insulated tank that stores hot water heated by the heat pump, with a much larger internal coil than a cylinder designed for a boiler. Heat pumps heat water to a lower temperature than boilers, typically around 45–55°C, so a bigger coil is needed to pass heat into the stored water quickly. A standard boiler cylinder would heat slowly and make the heat pump work harder than it should.
Cylinder sizes for County Antrim homes are based on the people living there and the bathrooms in daily use. Many homes in County Antrim with combi boilers have no airing cupboard, so the survey looks for the most practical cylinder space. In terraced homes around County Antrim and across County Antrim, slimline cylinders can fit spaces a standard model cannot.
Who it suits
- Households with older vented cylinders and loft tanks who want mains-pressure showers
- Every air-to-water heat pump installation, whatever the existing boiler
- Homes replacing a combi boiler that need space found for a cylinder
- Larger families or homes with two or more bathrooms
Grants and rules for heat pumps in Northern Ireland
The Boiler Upgrade Scheme covers England and Wales only, and there is currently no dedicated heat pump grant for homeowners in Northern Ireland. Our quote for a home in County Antrim is therefore shown without a grant deduction; if support becomes available we will tell you how it applies.
Installing heat pumps has been zero-rated for VAT in Northern Ireland since 1 May 2023, in line with the rest of the UK, until 31 March 2027. Northern Ireland has its own permitted development rules and building regulations, and we confirm what applies to your property at survey.
Heat pump hot water cylinders prices in County Antrim
These are guide prices for County Antrim, installed and including VAT. Your final price is fixed in a written quote after the survey and depends on the heat loss of the house, the radiators that need changing and where the unit goes.
| Work | Guide price |
|---|---|
| Heat pump hot water cylinder (supplied and fitted) | £1,150–£2,150 |
Supplied and fitted, inc VAT. Included in every full system price.
Towns we cover in County Antrim
We cover 11 towns in County Antrim for heat pump hot water cylinders. Each links to local guide prices and the grant position for Northern Ireland.
| Town | Postcode district | Nearest town | Midwinter daylight |
|---|---|---|---|
| Belfast | BT1 | Newtownabbey | 7 h 15 min |
| Lisburn | BT27 | Belfast | 7 h 16 min |
| Newtownabbey | BT37 | Belfast | 7 h 14 min |
| Carrickfergus | BT38 | Newtownabbey | 7 h 13 min |
| Ballymena | BT42 | Antrim | 7 h 12 min |
| Antrim | BT41 | Ballyclare | 7 h 13 min |
| Larne | BT40 | Carrickfergus | 7 h 12 min |
| Ballycastle | BT54 | Ballymoney | 7 h 07 min |
| Ballyclare | BT39 | Antrim | 7 h 13 min |
| Ballymoney | BT53 | Coleraine | 7 h 09 min |
| Portrush | BT56 | Portstewart | 7 h 07 min |
Heat pump hot water cylinders questions
Do I need good water pressure for an unvented cylinder?
Yes. An unvented cylinder runs at mains pressure, so it needs enough incoming pressure and flow to supply your taps and showers well. We measure your mains supply at the survey. If flow is low, options include a different cylinder type or an upgrade to the incoming supply pipe, which we explain before you commit.
Will I run out of hot water with a heat pump?
Not if the cylinder is sized to how your household uses hot water. Unlike a combi, hot water is stored, so very heavy use, such as several long showers back to back, can use up the stored volume before it reheats. Sizing for your busiest period, and timing reheats sensibly, avoids this for most homes.
I have a combi boiler. Where will the cylinder go?
Moving from a combi to a heat pump means finding space for a cylinder, usually somewhere around 600 mm square and up to about 2 m tall. Common choices are a bedroom or landing cupboard, a utility room, under the stairs or an integral garage. The surveyor looks at your layout and suggests options, including slimline models where space is tight.
How much does a heat pump cylinder cost?
A heat pump hot water cylinder has a guide price of £1,200–£2,200, installed and including VAT. In a full heat pump installation the cylinder is already included in the system guide price, so this figure mainly applies where a cylinder is replaced on its own. Capacity, coil design and the pipework needed affect where your price sits.