Heat pump repair is the diagnosis and fixing of faults in an air source heat pump, its water circuit, its controls or the hot water cylinder. Many faults have a simple cause, such as low system pressure, a blocked filter or a control setting, while others involve a failed sensor, pump, fan or circuit board.
For repeated faults in Merseyside, the engineer looks at the system design as well as the failed part. We repair heat pumps in Merseyside whoever installed them, including older monobloc and split systems. Heat pump owners in Merseyside can arrange a fault-finding visit at a rate agreed before an engineer attends.
Who it suits
- Systems losing pressure or needing frequent topping up
- Heat pumps installed by another company that need a second opinion
- Heat pumps showing an error code or fault light
- Rooms or hot water not getting warm enough
Grants and rules for heat pumps in England
In England the Boiler Upgrade Scheme gives £7,500 towards an air source heat pump (£9,000 if it replaces oil or LPG, from 21 July 2026 to 31 March 2027), and since 28 April 2026 a valid EPC is no longer needed. The grant is applied for by the MCS-certified installer and shown as a deduction on your quote.
Heat pump repairs prices in Merseyside
These are guide prices including VAT. The rate for your visit in Merseyside is confirmed before we book it, and any repair is priced in writing before parts are ordered.
| Repair | Guide price |
|---|---|
| Fault-finding visit and diagnosis | £90–£170 |
| Sensor or thermistor replacement | £120–£270 |
| Expansion vessel or pressure relief valve | £150–£340 |
| Circulating pump replacement | £240–£470 |
| Fan motor replacement | £290–£630 |
| Refrigerant leak repair and re-gas (split systems) | £340–£920 |
| Main control board (PCB) replacement | £440–£1,050 |
Inc VAT. The fault-finding rate is agreed before we attend; repairs are priced in writing before parts are ordered.
Towns we cover in Merseyside
We cover 14 towns in Merseyside for heat pump repairs. Each links to local guide prices and the grant position for England.
| Town | Postcode district | Nearest town | Midwinter daylight |
|---|---|---|---|
| Liverpool | L3 | Birkenhead | 7 h 29 min |
| Birkenhead | CH41 | Liverpool | 7 h 29 min |
| St Helens | WA10 | Prescot | 7 h 29 min |
| Southport | PR8 | Formby | 7 h 26 min |
| Wallasey | CH45 | Birkenhead | 7 h 29 min |
| Bootle | L21 | Wallasey | 7 h 28 min |
| Bebington | CH63 | Birkenhead | 7 h 30 min |
| Huyton | L36 | Prescot | 7 h 29 min |
| Kirkby | L32 | Maghull | 7 h 28 min |
| Prescot | L34 | Huyton | 7 h 29 min |
| Heswall | CH60 | Bebington | 7 h 30 min |
| Maghull | L31 | Kirkby | 7 h 28 min |
| Formby | L37 | Maghull | 7 h 27 min |
| Halewood | L26 | Huyton | 7 h 30 min |
Heat pump repairs questions
Why does my heat pump keep switching on and off?
Frequent starting and stopping, called short cycling, is usually caused by an oversized heat pump, low water flow, too many zones closing at once or controls set with too narrow a range. It reduces efficiency and wears components. An engineer can check the settings, flow rates and design, and can often improve it with control changes before any parts are needed.
Is ice on my heat pump a fault?
Some frost on the outdoor unit in cold, damp weather is normal, and the unit clears it with regular defrost cycles, often releasing a little vapour. It becomes a fault when thick ice builds up and does not clear, or when ice blocks the fan. That can point to poor airflow, a failed sensor, drainage problems or low refrigerant, and needs checking.
Do refrigerant repairs need a specialist?
Yes. Any work on a heat pump's refrigerant circuit, such as tracing a leak, replacing a component or re-gassing, must by law be done by an F-gas certified engineer where the refrigerant is fluorinated, such as R32; units using R290 (propane) need an engineer trained in flammable refrigerants. On split systems the refrigerant runs through pipes inside your home, so leaks there are more likely than on sealed monobloc units.
How much does a heat pump repair cost?
Heat pump repairs have a typical range of £90–£1,100, including VAT, depending on the part and labour involved. Sensor replacements sit at the lower end, while control boards and refrigerant repairs on split systems sit higher. Every repair starts with a fault-finding visit, with a guide price of £90–£180 for the first hour, and the repair is priced before work goes ahead.

