The trade-off is that the pipes between the outdoor unit and the house carry water, so they must be protected from freezing. That is done with glycol (an anti-freeze) in the system or with anti-freeze valves that release water from the outdoor pipework if it nears freezing, for example during a power cut in cold weather. Keeping the outdoor pipe run short and well insulated also helps efficiency.
Houses in County Armagh with a rear wall close to the cylinder location usually suit a monobloc unit with a short pipe run. A survey in County Armagh checks the unit position, pipe route and clearance zones together for homes across County Armagh. In exposed spots around County Armagh, frost protection for the outdoor pipework is chosen with the site in mind.
Who it suits
- Owners who want the simplest installation, with no indoor refrigerant
- Houses and bungalows with outdoor space close to where pipes enter the home
- Households that want to keep refrigerant work out of routine servicing
- Homes where the unit can sit within a short pipe run of the cylinder
Grants and rules for heat pumps in Northern Ireland
Northern Ireland does not have a dedicated heat pump grant for homeowners at present, and the Boiler Upgrade Scheme does not apply here. Heat pumps have sometimes been funded through the Northern Ireland Sustainable Energy Programme, so it is worth checking what is open when you enquire about a home in County Armagh.
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.
Monobloc heat pumps prices in County Armagh
Here are typical prices for monobloc heat pumps in County Armagh, installed and including VAT. Use the guide price tool for a figure based on your home, then a survey confirms it in writing.
| Home | Typical size | Installed guide price |
|---|---|---|
| 1–2 bedroom flat or small terrace | 4–5 kW | £9,200–£12,150 |
| 2–3 bedroom terrace or semi | 5–7 kW | £10,200–£13,100 |
| 3 bedroom semi or small detached | 6–9 kW | £11,650–£15,050 |
| 4 bedroom detached | 8–12 kW | £13,600–£17,450 |
| 5+ bedroom or larger older house | 11–16 kW | £16,000–£21,850 |
Installed, inc VAT: unit, cylinder, controls, minor pipework and commissioning. No dedicated heat pump grant currently applies in Northern Ireland.
Towns we cover in County Armagh
We cover 6 towns in County Armagh for monobloc heat pumps. Each links to local guide prices and the grant position for Northern Ireland.
| Town | Postcode district | Nearest town | Midwinter daylight |
|---|---|---|---|
| Craigavon | BT64 | Lurgan | 7 h 17 min |
| Portadown | BT62 | Craigavon | 7 h 17 min |
| Armagh | BT61 | Keady | 7 h 18 min |
| Keady | BT60 | Armagh | 7 h 19 min |
| Lurgan | BT66 | Craigavon | 7 h 17 min |
| Tandragee | BT63 | Portadown | 7 h 18 min |
Monobloc heat pumps questions
What is the difference between monobloc and split heat pumps?
A monobloc unit holds all of its refrigerant in the outdoor unit and sends heated water into the house. A split system has an outdoor unit and an indoor unit called a hydrobox, connected by refrigerant pipes, with heat passed to water indoors. Monobloc installs are simpler; splits avoid outdoor water pipes but need an F-gas certified engineer for the refrigerant work. Our monobloc vs split guide compares them.
Is glycol or anti-freeze valves the better option?
Neither is right for every home. Glycol gives reliable frost protection without draining but slightly reduces efficiency and needs its concentration checked at servicing. Anti-freeze valves keep the system water plain but release water if pipes near freezing during a power cut, so the system then needs refilling. The installer recommends one based on the unit, pipe run and how exposed the site is.
How far can a monobloc unit be from the house?
Usually as close as practical, because water pipes outside lose heat and need frost protection. Manufacturers set limits on pipe length and size, and longer runs need larger, better-insulated pipes. Most homes site the unit against or near an outside wall close to where the pipes enter. If the only good position is far from the house, a split system may suit better.
Are monobloc heat pumps covered by grants?
Yes. Monobloc units are air-to-water heat pumps, so in England and Wales they are covered by the Boiler Upgrade Scheme grant of £7,500 for eligible homes, or £9,000 when replacing oil or LPG heating within the published dates. In Scotland, Home Energy Scotland funding requires an MCS-certified installer and products. There is no dedicated homeowner heat pump grant in Northern Ireland at present.

